If you have any questions not covered by this FAQ, feel free to ask!
How do I search for a mod I want to download?
Look around in this forum for the thread belonging to the mod you want to install. If you can't find it, I suggest you google the name of the mod. For example, google "TooManyItems". You can also check out tutorials and reviews for the mod on YouTube; those often have download links in their descriptions. If you're googling mods, ensure you get to the right site - most likely the mod has a Minecraft Forums topic, PlanetMinecraft page or CurseForge page. If it appears in the search results, click your way to it. It should look something like this:
Notice how it says below the title in green text, "www.minecraftforum.net". This lets you know that the mod page is on Minecraft Forums, a trusted site for mod downloads. Make sure you follow the guidelines in thesecurity sectionto keep your computer free of viruses.
How do I download mods from Minecraft Forums?
Once you've found the Minecraft Forums topic containing the mod, look for a "Downloads" section on the first post. Once you've found it, ensure you're downloading the mod for the correct version of Minecraft. Here's a look from the TooManyItems downloads section:
You'll see there are several versions to select from. The first thing you'll have to ask yourself is: which version of Minecraft am I using? When you play Minecraft, this will always show in the bottom right corner of the main menu:
In this case, I'm using Minecraft 1.7.2. If we look back at the TooManyItems' downloads section, we'll see that a 1.7.2 version is available, titled "For 1.7.2 non-Forge version". Click on it. You'll end up on a page with a blue bar up top titled "adf.ly" - please see the next question for a short introduction to what this is.
What is AdFly?
In the previous question, when I told you to click on the download link, you were sent to a page titled "adf.ly". You're probably wondering what this is, and how you deal with it.
First of all, I wouldn't recommend staying on an AdFly page a second longer than necessary, so I'll show you how to get past it so you can download your mod. Look in the top right corner of the page, on the blue bar. There will most likely be a countdown. Once it's completed, press the green or yellow "Skip ad" button in the top right corner.
But what is actually AdFly? AdFly is a link shortening service that, in addition to shortening links, gives link-makers money for people clicking on their links. For every 1000 clicks a link receives, the author of said link gets US$ 4.00 in revenue. Many mod makers uses AdFly to try and earn money for free through people downloading their content. Many mod authors prefer to use Curse, or have their own sites, for claiming ad revenue for their mods, while others do not put any advertisements on their downloads or sites at all. Several modders also use AdFly in addition to Curse or a personal website.
You're probably wondering why I told you to get off AdFly as soon as possible. The reason is the ads served through AdFly may in rare cases contain malicious scripts, which could potentially infect your computer with a virus or a trojan. You can read more about this in the security considerations section further down on this page.
What is Forge?
Minecraft Forge, often just called Forge, is a mod loader for Minecraft. It's fair to say that most mods use Forge to function. Mods using Forge have the major advantage of ease of installation - installing Forge mods is nothing more complicated than a simple drag-and-drop between two folders. Mods not using any mod loaders are called vanilla mods - they don't taste like vanilla, the term refers to the mods just being plain. These mods are much harder to install than Forge mods. It's worth noting that Minecraft Forge has very limited documentation, which can make troubleshooting difficult.
Forums user Botjoe helpfully recommends using separate profiles and game directories if you are playing with different versions of Forge. Please see the section on game directories for more help regarding this.
LiteLoader is a mod loader similar to Minecraft Forge, but is much smaller and provides more basic support. Mods for LiteLoader are as easy to install as mods for Forge - a simple drag and drop between folders. LiteLoader is not used by very many mods, and some loaders are now unsupported.
To install Forge, you should head over to the Minecraft Forge download page, linked above. Choose the Installer option for the Recommended release:
Run the installer when it's been downloaded. When the installer opens, you'll see a menu with three options: "Install client", "Install server" and "Extract". Select the "Install client" option and press OK. Forge will now install itself.
How do I install LiteLoader?
To install LiteLoader, head over to the LiteLoader forum topic (linked above) and look for the download section. Download the installer and run it. The installer will open with a few options; "Install LiteLoader" and "Extract LiteLoader". Select the "Install LiteLoader" option. If you also have Forge installed, check the "Chain to Minecraft Forge" checkbox and press OK to install.
How do I install Forge and LiteLoader mods?
Both Forge mods and LiteLoader mods are installed in the same way:
Start by downloading and installing Forge/LiteLoader (see above).
Look for a folder named "mods". If there is no folder named mods, create it.
Copy the mod you downloaded into the mods folder.
To play Minecraft with the mods installed, select the Forge or LiteLoader profile in the bottom left corner of the Minecraft launcher, then press play.
How do I install vanilla mods?
Installing vanilla mods is difficult if you don't know how.
Open up the "versions" subfolder and find the folder with the Minecraft version you're installing the mod for. Ensure you select the right folder!
Make a copy of this folder and name it something like "1.7.2_mods" (I'm using Minecraft 1.7.2, hence 1.7.2 in the name). Try not to use spaces in the name.
Open the folder you just created and rename the two files inside in the same way you renamed the folder: 1.7.2_mods (it must be the name you chose). Do not remove the .json ending on the file that ends with .json! The two files should now look something like this:
Open the file that ends with ".json" in Notepad or Notepad++.
Look for a line near the top starting with "id":
Replace the version number on that line with the name of the file (in this case, "1.7.2_mods").
Save the file and exit.
If you're on Mac or Linux, you can skip this step. Download and install 7-zip or WinRAR (I prefer 7-zip - it's free!).
Open the file that does not end in ".json" with 7-zip or WinRAR. If you're using Mac or Linux, use your system's archive manager to open the file.
Open the mod zip file you downloaded using the same program (7-zip, WinRAR or the system archive manager).
Select all the files in the mod ZIP file by pressing Ctrl+A. Then drag them over to the 1.7.2_mods file.
Delete the folder META-INF, with all contents, from the 1.7.2_mods window.
Close both windows.
Open the Minecraft launcher.
In the bottom left corner of the launcher, press the New profile button.
Name the profile "1.7.2 mods" (or something else descriptive).
Select "release 1.7.2_mods" from the "Use version" drop down box.
Press Save profile.
To play Minecraft with the mod(s) installed, simply select the "1.7.2 mods" profile in the bottom left corner of the launcher, and press Play.
How do I install vanilla mods in Minecraft Forge?
You may have thought that following the procedure above would've worked, but if you do it with Forge specifically, Minecraft will crash. Here's how you do it.
Start by downloading and installing Forge (see above), if you haven't already.
Play Minecraft! Your mods should now be installed on top of Forge.
Please be aware that when installing vanilla mods in Forge, you'll likely overwrite some of Forge's functionality. This could cause mod conflicts and crashes that would usually not appear in a healthy Forge installation.
How do I find my .minecraft folder?
There are three ways to find the .minecraft folder:
Method 1: Via resource packs menu
Open the Minecraft launcher and play the game.
Go to the Resource packs menu.
Press the "Open resource packs folder" button.
Go up one level.
Method 2: Finding it manually
On Windows: Press Windows+R, type the following:
%appdata%\.minecraft
and press Enter.
On Mac: Navigate to ~/Library/Application Support/minecraft. This is your .minecraft folder.
On Linux: Navigate to ~/.minecraft. This is your .minecraft folder.
Method 3: Using the launcher (recommended!)
Open the Minecraft launcher.
Click on the "Edit profile" button in the bottom left corner of the launcher window.
Click on "Open Game Dir" in the bottom right of the window that appears.
Can I use another folder than .minecraft for my game data?
Absolutely! If you want to put your game files in another folder, then, in the Minecraft launcher, click on the Edit profile button in the bottom left corner. Check the box next to "Game Directory" and insert the full path to where you want your game files (mods, saves, screenshots, resource packs etc.) stored. Click on Save Profile when you're done.
Note: You may have to move your existing "saves", "mods", "screenshots", "resourcepacks" and other relevant folders from .minecraft to the new directory you've chosen if you have already played with .minecraft as your game directory previously.
Forums user Botjoe helpfully informs that using multiple different game profiles with different game directories can be very useful if you like to switch between multiple versions of modded Minecraft, or different collections of mods. For instance, having one game directory called something like "FTBInfinity" and another called "The1.7.10Pack" for each of those modpacks will stop you from accidentally loading the wrong world in the wrong modpack, corrupting the world. If multiple players play on the same computer, changing game directories can also be useful to ensure that the players do not play on each other's worlds by accident.
Important:What should I watch out for when I download mods?
There are a lot of traps that are easy to end up caught in when downloading mods:
Never download any mods without having an anti-virus enabled.
Windows users should take great care to have an anti-virus, since Windows is the most popular operating system and therefore the one most hackers want to infect with a virus.
Never run EXE files claiming to be mod installers.
These are in 99% of cases viruses. Upload the executable file to VirusTotal to scan it for viruses.
Only run installers for mods you have used before and trust, and only run them if the installer was made by the mod creator himself.
Do not run installers for any mod if the uploader has few posts and/or very few mods exist for the targeted Minecraft version.
Topics on Minecraft Forums with positive feedback from other forum users are probably trustworthy.
Also beware of which sites you download mods from. Always download from the official download page. The sites listed below are well-known mod hosting or linking sites which can be trusted, except if the above criteria make you worry (i.e. executable files have been seen on these forums, although very rarely, and in those cases, be extra careful).
If the mod's official topic or page links to another domain for downloading, chances are that it's safe to download.
If the site you are downloading from is on this list (link) , do not download. The sites listed there are known for stealing mods from the original authors and may even be infected with malware and viruses.
Will mods work even if they're not made for my Minecraft version?
The simple answer is no. The reason why is because Minecraft's source code is encoded. Minecraft is encoded through obfuscation; that is changing human readable names of things into seemingly random series of letters, like "Minecraft" may be changed to "azd" and "GuiNewChat" into "bav". In mods' raw source code, there are references to these obfuscated names. The problem is that these names change over time - there are new names for everything with every new release.
If the mod source code references "bav", it would correctly reference "GuiNewChat" (the chat window) in the Minecraft version it's designed for. However, because the obfuscation pattern changes between each release, in another Minecraft version it might reference "GuiButton" instead (Minecraft buttons). This causes problems because the mod's source code doesn't automatically detect that it's referencing the wrong thing.
If you frequently play different Minecraft versions, it's recommended that you separate their game directories so that you do not accidentally load the wrong Minecraft world into a different version of the game.
What is MCP, and why is it so important?
MCP is short for Mod Coder Pack. What this does is help mod developers develop mods for Minecraft easily. If you look at the question above this, you'll see that the Minecraft source code is obfuscated. Developing mods without MCP isn't impossible, rather very difficult, and few want to do that work. What MCP does is that it acts like a translator, translating the meaningless, obfuscated names in the source code and turns them into names modders can understand.
MCP is also the tool that decompiles Minecraft. In terms of software, decompiling is reverse engineering - it is turning the actual program back into source code form. Modding compiled code directly is probably the toughest form of programming there is - compiled Java code is called bytecode, and bytecode is simply a long series of bytes. An example of bytes could be "�ˣ�#M6u�" - now that isn't proper Java bytecode, but is what one could expect from looking at raw class files if opened in Notepad. Being able to understand that and edit it is a huge feat in itself. MCP also does the work of recompiling the decompiled source code back to bytecode form, so Java can understand it.
MCP is written in Python, and is being developed by Searge, ProfMobius, IngisKahn, Fesh0r, ZeuX and R4wk. The community also contributes mappings from obfuscated names to human readable names for MCP. Their official website is http://mcp.ocean-labs.de/.
Why can't mod authors avoid using the Mod Coder Pack and Forge, to update faster?
Modding without MCP, Forge, etc. is, to put it short, extremely difficult. Mainly because the Minecraft source is encoded, and while you can mod in this encoded source, few want to put forth any effort to try doing so. Minecraft is encoded through obfuscation; that is changing human readable names of things into seemingly random series of letters, like "Minecraft" may be changed to "azd" and "GuiNewChat" into "bao". You may be thinking that it shouldn't be too difficult to learn these names, or at least the most important ones, and indeed, I pulled those two names of the top of my head simply because I've worked a lot of them. If I want to access the Minecraft data directory (.minecraft), I know I should look for "azd.w," which translates to "Minecraft.mcDataDir".
Learning a few is easy enough. Learning many (like, how to render text on screen, adding textures to blocks, making interactive GUIs, etc.) is a whole other story. De-obfuscating the source code is like translating a text from one language to another. Learning some words is easy, learning many is hard. And this is where MCP comes in. MCP is short for Mod Coder Pack, and functions much the same way as an automated translator. It de-obfuscates everything for you, and as an added bonus; from 1.7.2 and on it also categorizes the code for you, based on what purpose each code file serves. To use a metaphor for this, I could say that it picks up a pile of 1000+ Latin documents from the floor, translates everything to English before sorting it similarly to like in an archive. This lets you have something that translates Latin to English, so you can work on it, and then back again to Latin when you're done, instead if you having to learn Latin to perform corrections in the documents.
There's also another, very good reason to not learn the obfuscated language yourself. Between the Minecraft versions, the obfuscation changes, so you'll have to learn what everything does all over again. If the new pile of documents is in Afrikaans, I doubt you'd want to learn that new language when you know you're going to get your hands on a translator to do the job for you in not too long time.
If you wonder where Forge comes in play, I'm coming to that now. Forge is a so-called API. API stands for Application Programming Interface, and as you may guess from its name, it's used to make programming easier by providing a set of functions to take use of. One such function would be adding a block, or a dimension, or a mob to the game. It allows the mod to add things in a very easy way and with much less messy code than it would have to if it was to add blocks without Forge. It also allows putting all the code for adding things into a single class file, meaning it is easier for the developer to keep track of what he's doing. In vanilla Minecraft, not only would he need to use multiple files, he also needs to keep track of which class files he's modifying.
Another very neat function of Forge is that it lets you use many (up to hundreds) of mods at the same time without either one conflicting with each other. If you had several block adding vanilla mods, they all probably would need to edit the block registry file. As the code of multiple mods can't easily be merged together, only one mod would work and most likely the game would also crash. Finally, there's another reason to use Forge above vanilla mods. There used to be plenty of vanilla mods up until Minecraft 1.6. From there on, the game required a whole new launcher to play properly, and this launcher introduced a new way of keeping track of the Minecraft versions. Installing mods was no longer as straight forward as putting the class files in a jar file and deleting a folder. Now, you had to make copies of the Minecraft version you needed, actually change something in a code file and add a new profile to the launcher. Forge mods still just have to be dropped into the mods folder in .minecraft.
How do I solve ID conflicts in Forge 1.6.4 (or earlier) mods?
Originally posted by MCforfreeuserhereand modified to fix some mistakes.
After installing a new mod, you might have some ID conflict. Your added block might do something different or crash when you interact with it. It may also crash directly at the Mojang screen. You might even see a mob doing something another mob should've done (this is rare, and when it happens you rarely can fix it). All these types of behavior are caused by ID conflicts.
Everything in the world of Minecraft has an ID. Blocks have, items have, entities have too. At the Mojang screen, Forge creates a list of those IDs from the game and the mods. If two things have the same ID, Forge will crash because it doesn't know what to do. If it is an item ID conflict, Forge simply overwrites the block. If it is a block ID conflict, it crashes at the Mojang screen. If it is an entity ID conflict, Forge overwrites the mob.
You can scan for ID conflict by opening the log file which name is 'ForgeModLoader-client-0.log', located in the .minecraft folder. You can open it using Notepad, or another text editor. Then, use the find function by pressing Ctrl+F. Fill the 'Find' box with 'conflict'. Do the search. You may find some. It will look like this:
2014-01-19 18:12:58 [INFO] [STDOUT] CONFLICT @ 1269 item slot already occupied by net.minecraft.item.ItemBlock@f5b91 while adding org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab@44bfe9
2014-01-19 18:12:58 [INFO] [fml.ItemTracker] The mod millenaire is overwriting existing item at 1525 (org.millenaire.common.block.BlockDecorativeSlab from millenaire) with org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab
You can see that Forge overwrites the blocks. If they were items, you would find a crash report after the above lines.
To fix it, go to 'config' folder and find the questioned mod's config file. Look for the numbers above (in this case, 1269). Change it to something else. However, the ID lists have limits - if you put an ID outside the limit, the game crashes. Block ID limit is 128-4095, item ID limit is 128-65535. Also, ensure you don't choose any ID listed on this Minecraft Wiki page, as those are reserved by the game itself (things like gold ore, enchanting table, dirt, etc.). After you change the number, save and exit the config. Run the game again. If it still conflicts, repeat the process.
Mods should start using IDs from 256 and higher, to prevent problems with Minecraft itself. Mods for Minecraft 1.7 and above do not typically suffer from ID conflict issues.
What are IDs, and what are they used for?
In Minecraft terms, IDs are unique numbers or letters used by the game to identify blocks, items, mobs, dimensions and other things. Think of them as barcodes on cardboard boxes: All the boxes look the same, but whatever is inside them varies. So how would you know what's inside? You could place barcodes on the boxes. Scan the barcode, and you'll know what's inside the box. That's pretty much exactly what Minecraft does. The game finds what seems to be some kind of block, and then it scans its ID and figures out that "hey, that's a grass block".
IDs in Minecraft consist of numbers and letters. From Minecraft was released in 2009, the game used numbers to keep track of what things were. Everything from 0-255 was a block, everything from 256-65535 was an item. Dimensions had their own system, 0 representing the overworld, -1 the Nether, and 1 the End. Monsters and animals shared their own system too. This system was used until the release of Minecraft 1.7. From that version and on, blocks and items weren't referred to by numbers, but by actual names. Gold ore, for instance, used to have the ID '14', but this was changed to 'minecraft:gold_ore'. Air, which counts as a block, used to have the ID '0', but this was changed to 'minecraft:air'. Not only did this make it easier for people to remember the IDs of things, it also made it possible to install mods without having the notorious ID conflicts.
The mod I installed crashes my game! What should I do?
What to do in this case depends on what kind of mod that's crashing. If we're speaking of a Forge mod, then first of all ensure there are no ID conflicts. You can identify ID conflicts and fix them by looking in the solving ID conflicts section. If it's a vanilla mod (one you install straight into the Minecraft jar, ensure you've deleted the META-INF folder in the jar file and that you carefully followed the instructions in the installing vanilla mods section. If you're confident that you've done it right, then check the following:
The version of the mod you're installing must correspond to the Minecraft version you're playing.
You must have installed all dependencies (like Forge, and various other mods) required for the mod to work.
If you're sure about this too, you should report the crash to the mod developer. For more information on how to submit a useful crash report, please see the next section. Remember that there is no way a mod developer can fix a bug if there is no one around to tell him that said bug even exists at all.
How do I report a crash in a useful way?
If your game crashes, you'll be returned to the Minecraft launcher. There should be a crash report visible in it. One important thing to remember is to include this in your post. Posting this in plain text on your post will take up a lot of space, so it is highly recommended that you wrap it in spoiler tags. How, you ask? Well, in your forum post, follow this template:
YOUR CRASH REPORT HERE
This will display a small rectangular bar with a Show button above, so people can check out your crash without it covering the entire page automatically.
If there, for some reason, are no crash reports, go to the Developer Console tab of the launcher and paste that in instead.
Another thing you should (must) post is what triggered the crash. What were you doing prior to the crash? Did you craft a block using red sand and compressed iron ore on a green crafting table, and after that, you placed it on the ground and broke it with an obsidian pickaxe? If so, then say so. There are often several ways for a specific thing to happen, but there may well be only one specific scenario where a crash occurs. The developer will figure out if it only happens with the procedure you gave him, or if it's a generic crash that happens with, say, any kind of pickaxe.
When the developer responds: If he is asking of you more information, then give him that information. Don't just tell him that "no it just doesn't work pls fix!!!!" because that won't help him at all. I don't have time to explain everything a developer needs to fix a bug, but if you're interested, I'd highly suggest giving this page a read-through: http://www.chiark.gr...atham/bugs.html
How do I downgrade Minecraft?
In the Minecraft Launcher, look in the bottom left for the profile selector. Press New Profile. Name the profile to something understandable (like, "1.6.4"). Then, select the preferred Minecraft version from the Minecraft Version dropdown. Save the profile. Whenever you want to play this version, simply select the version from the profile selector and hit Play.
Warning: Do not play worlds you created in a newer version of Minecraft when you play an old version. Doing this will cause serious problems and may result in unfixable damage to your entire map. This will cause you to permanently lose all your work. Playing newer Minecraft version maps in older versions of Minecraft may also cause the game to crash. If you frequently play different versions of Minecraft, consider setting up different profiles in the launcher that use different game directories, so that the worlds from one version cannot be accidentally loaded into another version of the game.
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Very well-written and helpful post. As a user of ~250 mods, I can affirm that all of this is correct. I actually never knew how to install a vanilla mod. I personally believe that this should be pinned to the top of the Mods forum section to help out newer mod users. Maybe you could add in a section discussing things like common crashes, Block ID conflicts, how to use config files, and stuff like that? I fully support any effort to educate and help out new mod users, as I remember the time I struggled to install Buildcraft for 1.2.5 for the first time. Good job
Probably shouldn't make the links to the malicious sites actual links, as just browsing to one to check it out could initiate serious trouble.
And a good rule of thumb is that if a mod has been vetted here on the forums - As in actually downloaded and tested and commented on by forum-goers, it's most likely safe. Some of the third-party mod sites may make it look like a mod has been vetted, but often times the creator of the virus just logs in with multiple accounts to comment on his own 'mod'. That's a lot harder to do here on this forum where everyone watches out for everyone's back.
Very well-written and helpful post. As a user of ~250 mods, I can affirm that all of this is correct. I actually never knew how to install a vanilla mod. I personally believe that this should be pinned to the top of the Mods forum section to help out newer mod users. Maybe you could add in a section discussing things like common crashes, Block ID conflicts, how to use config files, and stuff like that? I fully support any effort to educate and help out new mod users, as I remember the time I struggled to install Buildcraft for 1.2.5 for the first time. Good job
Thank you for kind and uplifting words
You have some good ideas - I'll do some research into how ID conflicts are solved, common configuration formats and common types of crashes, how to report crashes etc. It will probably take a while, but maybe tomorrow or in a few days I may have this done.
Probably shouldn't make the links to the malicious sites actual links, as just browsing to one to check it out could initiate serious trouble.
And a good rule of thumb is that if a mod has been vetted here on the forums - As in actually downloaded and tested and commented on by forum-goers, it's most likely safe. Some of the third-party mod sites may make it look like a mod has been vetted, but often times the creator of the virus just logs in with multiple accounts to comment on his own 'mod'. That's a lot harder to do here on this forum where everyone watches out for everyone's back.
You have a good point, too - I'll make sure to add your considerations to the main post as soon as I have enough time to formulate it in a nice way. As for the links, I'll fix that right away as that is a serious security problem and should be fixed as soon as possible.
Rollback Post to RevisionRollBack
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Very useful. I'm sure this will help with a lot of issues and generally help people out!
Thank you I was hoping it would prove to be useful!
Rollback Post to RevisionRollBack
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
I added some information on cross-Minecraft-version incompability, what MCP is and why it's really neccessary. I'm still looking into how to resolve ID conflicts, but if you have any other questions or feedback, feel free to reply!
Also, if you feel you could contribute to this post, please reply, I'd highly appreciate!
Rollback Post to RevisionRollBack
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Requirement:
Comprehension of the above guide
A played Minecraft+Forge version
Usually, you can configure mods. The config is saved in 'config' folder inside '.minecraft'.
After installing a new mod, you might have some ID conflict. Your added block might do something different or crash when you interact with it. It may also crash directly at the Mojang screen. You might even see a mob doing something another mob should've done(this is rare, and when it happens you rarely can fix it). All this are caused by ID conflicts.
Everything in the world of Minecraft has an ID. Blocks have, items have, entities have too. At the Mojang screen, Forge creates a list of those IDs from the game and the mods. If two thing have the same ID, Forge will error because it don't know what to do. If it is a block ID conflict, Forge simply overwrites the block. If it is an item ID conflict, it crashes at the Mojang screen. If it is an entity ID conflict, Forge overwrites the mob.
You can scan for ID conflict by opening the log file which name is 'ForgeModLoader-client-0.log'. You can open it using Notepad. Then, use the find function by pressing Ctrl+F. Fill the 'Find' box with 'conflict'. Do the search. You may find some. It will look like this:
2014-01-19 18:12:58 [INFO] [STDOUT] CONFLICT @ 1269 item slot already occupied by net.minecraft.item.ItemBlock@f5b91 while adding org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab@44bfe9
2014-01-19 18:12:58 [INFO] [fml.ItemTracker] The mod millenaire is overwriting existing item at 1525 (org.millenaire.common.block.BlockDecorativeSlab from millenaire) with org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab
You can see that Forge overwrites the blocks. If it was items, you would find a crash report after the above lines.
To fix it, go to 'config' folder and find the questioned mod's config file. Look for the numbers above(in this case, 1269). Change it to something else. However, the ID list have a limit. If you put an ID outside the limit, the game crashes. Block ID limit is 256-4095(4096?), item ID limit is 256-65536. After you change the number, save and exit the config. Run the game again. If it still conflicts, repeat the process.
Using Vanilla Mods:
If the mod has a config file, you can try changing the conflicting IDs to something no lower than 512(?). If the mod doesn't has a config... deal with it.
That's all I can type. Good guide!
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Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
Requirement:
Comprehension of the above guide
A played Minecraft+Forge version
Usually, you can configure mods. The config is saved in 'config' folder inside '.minecraft'.
After installing a new mod, you might have some ID conflict. Your added block might do something different or crash when you interact with it. It may also crash directly at the Mojang screen. You might even see a mob doing something another mob should've done(this is rare, and when it happens you rarely can fix it). All this are caused by ID conflicts.
Everything in the world of Minecraft has an ID. Blocks have, items have, entities have too. At the Mojang screen, Forge creates a list of those IDs from the game and the mods. If two thing have the same ID, Forge will error because it don't know what to do. If it is a block ID conflict, Forge simply overwrites the block. If it is an item ID conflict, it crashes at the Mojang screen. If it is an entity ID conflict, Forge overwrites the mob.
You can scan for ID conflict by opening the log file which name is 'ForgeModLoader-client-0.log'. You can open it using Notepad. Then, use the find function by pressing Ctrl+F. Fill the 'Find' box with 'conflict'. Do the search. You may find some. It will look like this:
2014-01-19 18:12:58 [INFO] [STDOUT] CONFLICT @ 1269 item slot already occupied by net.minecraft.item.ItemBlock@f5b91 while adding org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab@44bfe9
2014-01-19 18:12:58 [INFO] [fml.ItemTracker] The mod millenaire is overwriting existing item at 1525 (org.millenaire.common.block.BlockDecorativeSlab from millenaire) with org.millenaire.common.block.BlockDecorativeSlab$ItemDecorativeSlab
You can see that Forge overwrites the blocks. If it was items, you would find a crash report after the above lines.
To fix it, go to 'config' folder and find the questioned mod's config file. Look for the numbers above(in this case, 1269). Change it to something else. However, the ID list have a limit. If you put an ID outside the limit, the game crashes. Block ID limit is 256-4095(4096?), item ID limit is 256-65536. After you change the number, save and exit the config. Run the game again. If it still conflicts, repeat the process.
Using Vanilla Mods:
If the mod has a config file, you can try changing the conflicting IDs to something no lower than 512(?). If the mod doesn't has a config... deal with it.
That's all I can type. Good guide!
Thank you so much for your valuable contribution! I reworded it a little, fixed some typos, and added it to the main post. I didn't add the vanilla instructions, seeing as one can only have one block adding vanilla mod installed at a time without crashing, because all of them would have to override the block registry in some way or the other.
+ Added info on resolving ID conflicts in Forge
+ Added info on what IDs actually are
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I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Note that Forge reserves 0-128 for vanilla blocks, so it must be '128-4095' not what I typed. Items are '128-65535'. Sorry.
One more. Block ID limit is 128-4095, so it is possible to have a block which ID is 4095. So this:
Everything from 0-255 was a block, everything from 256-65535 was an item.
is not true.
Can you also add a note? [Air is actually a block and its block ID is 0.]
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Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
Note that Forge reserves 0-128 for vanilla blocks, so it must be '128-4095' not what I typed. Items are '128-65535'. Sorry.
One more. Block ID limit is 128-4095, so it is possible to have a block which ID is 4095. So this:
Everything from 0-255 was a block, everything from 256-65535 was an item.
is not true.
Can you also add a note? [Air is actually a block and its block ID is 0.]
Added. Thanks again However, one thing to note; vanilla uses block IDs from 0 to 175 currently. It also uses item IDs 256 through 422 and 2256 to 2267. Should I possibly include that in the main post?
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I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Added. Thanks again However, one thing to note; vanilla uses block IDs from 0 to 175 currently. It also uses item IDs 256 through 422 and 2256 to 2267. Should I possibly include that in the main post?
It's up to you, but I think you should. More knowledge for the people, y'know.
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Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
It's up to you, but I think you should. More knowledge for the people, y'know.
Sorry for not being here earlier, but I've been busy with the copyright thread and school work. Will make sure to link to the wiki page on data values as soon as I'm on my laptop, because posting and editing on an iPad is bordering to the impossible due to some JavaScript ruining everything.
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I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Oh, I remember you campaigning against Guff's copyright stuff. Honestly, I see that as a rant.
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Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
Oh, I remember you campaigning against Guff's copyright stuff. Honestly, I see that as a rant.
I don't know what Guff says, but I'm by all means for copyright and have proven people wrong a few times there. However, I'd like to keep that discussion out of this topic.
Rollback Post to RevisionRollBack
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Upon usual circumstances I would request this be moved. However, because it is so helpful, detailed, and great for n00bs that don't know how to mod via easy access, I request a sticky.
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Watch this! I can make your read this text! See? MAGIC! You have to use your jetpack! WOOSH!
Upon usual circumstances I would request this be moved. However, because it is so helpful, detailed, and great for n00bs that don't know how to mod via easy access, I request a sticky.
Thank you :')
Rollback Post to RevisionRollBack
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Can you put your current log file to Pastebin, MatHatrim?
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Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
This is an issue I've never heard about(or maybe not)... Do you mind getting newer version of Forge? This may not a problem with mods, so I can barely help. And, by logs I meant ForgeModLoader-client logs which appear on your .minecraft folder. Sorry for the confusion, but that piece of log shows nothing about errors. Can you get that one? Open it, press Ctrl+A, copy it, and paste it in Pastebin. Thank you for your acknowledgement in this guide!
bilde, can you add some basic BBCode tutorial on the front post?
Modest Texturer, Modeler, and Idea Provider. Can someone buy me Terraria, Borderlands 2, Goat Simulator, or Dead Island? Check my Profile for my contents, which includes a(n outdated) texture pack and a mod request! OcD Simple Add-On!
Frequently asked questions
Welcome to my FAQ for downloading and installing mods! I hope you like it
Table of contents:
If you have any questions not covered by this FAQ, feel free to ask!
How do I search for a mod I want to download?
Look around in this forum for the thread belonging to the mod you want to install. If you can't find it, I suggest you google the name of the mod. For example, google "TooManyItems". You can also check out tutorials and reviews for the mod on YouTube; those often have download links in their descriptions. If you're googling mods, ensure you get to the right site - most likely the mod has a Minecraft Forums topic, PlanetMinecraft page or CurseForge page. If it appears in the search results, click your way to it. It should look something like this:
Notice how it says below the title in green text, "www.minecraftforum.net". This lets you know that the mod page is on Minecraft Forums, a trusted site for mod downloads. Make sure you follow the guidelines in the security section to keep your computer free of viruses.
How do I download mods from Minecraft Forums?
Once you've found the Minecraft Forums topic containing the mod, look for a "Downloads" section on the first post. Once you've found it, ensure you're downloading the mod for the correct version of Minecraft. Here's a look from the TooManyItems downloads section:
You'll see there are several versions to select from. The first thing you'll have to ask yourself is: which version of Minecraft am I using? When you play Minecraft, this will always show in the bottom right corner of the main menu:
In this case, I'm using Minecraft 1.7.2. If we look back at the TooManyItems' downloads section, we'll see that a 1.7.2 version is available, titled "For 1.7.2 non-Forge version". Click on it. You'll end up on a page with a blue bar up top titled "adf.ly" - please see the next question for a short introduction to what this is.
What is AdFly?
In the previous question, when I told you to click on the download link, you were sent to a page titled "adf.ly". You're probably wondering what this is, and how you deal with it.
First of all, I wouldn't recommend staying on an AdFly page a second longer than necessary, so I'll show you how to get past it so you can download your mod. Look in the top right corner of the page, on the blue bar. There will most likely be a countdown. Once it's completed, press the green or yellow "Skip ad" button in the top right corner.
But what is actually AdFly? AdFly is a link shortening service that, in addition to shortening links, gives link-makers money for people clicking on their links. For every 1000 clicks a link receives, the author of said link gets US$ 4.00 in revenue. Many mod makers uses AdFly to try and earn money for free through people downloading their content. Many mod authors prefer to use Curse, or have their own sites, for claiming ad revenue for their mods, while others do not put any advertisements on their downloads or sites at all. Several modders also use AdFly in addition to Curse or a personal website.
You're probably wondering why I told you to get off AdFly as soon as possible. The reason is the ads served through AdFly may in rare cases contain malicious scripts, which could potentially infect your computer with a virus or a trojan. You can read more about this in the security considerations section further down on this page.
What is Forge?
Minecraft Forge, often just called Forge, is a mod loader for Minecraft. It's fair to say that most mods use Forge to function. Mods using Forge have the major advantage of ease of installation - installing Forge mods is nothing more complicated than a simple drag-and-drop between two folders. Mods not using any mod loaders are called vanilla mods - they don't taste like vanilla, the term refers to the mods just being plain. These mods are much harder to install than Forge mods. It's worth noting that Minecraft Forge has very limited documentation, which can make troubleshooting difficult.
Forums user Botjoe helpfully recommends using separate profiles and game directories if you are playing with different versions of Forge. Please see the section on game directories for more help regarding this.
Minecraft Forge can be downloaded from http://files.minecraftforge.net/.
What is LiteLoader?
LiteLoader is a mod loader similar to Minecraft Forge, but is much smaller and provides more basic support. Mods for LiteLoader are as easy to install as mods for Forge - a simple drag and drop between folders. LiteLoader is not used by very many mods, and some loaders are now unsupported.
LiteLoader can be downloaded from http://www.minecraft.../topic/1868280-.
How do I install Forge?
To install Forge, you should head over to the Minecraft Forge download page, linked above. Choose the Installer option for the Recommended release:
Run the installer when it's been downloaded. When the installer opens, you'll see a menu with three options: "Install client", "Install server" and "Extract". Select the "Install client" option and press OK. Forge will now install itself.
How do I install LiteLoader?
To install LiteLoader, head over to the LiteLoader forum topic (linked above) and look for the download section. Download the installer and run it. The installer will open with a few options; "Install LiteLoader" and "Extract LiteLoader". Select the "Install LiteLoader" option. If you also have Forge installed, check the "Chain to Minecraft Forge" checkbox and press OK to install.
How do I install Forge and LiteLoader mods?
Both Forge mods and LiteLoader mods are installed in the same way:
To play Minecraft with the mods installed, select the Forge or LiteLoader profile in the bottom left corner of the Minecraft launcher, then press play.
How do I install vanilla mods?
Installing vanilla mods is difficult if you don't know how.
Replace the version number on that line with the name of the file (in this case, "1.7.2_mods").
To play Minecraft with the mod(s) installed, simply select the "1.7.2 mods" profile in the bottom left corner of the launcher, and press Play.
How do I install vanilla mods in Minecraft Forge?
You may have thought that following the procedure above would've worked, but if you do it with Forge specifically, Minecraft will crash. Here's how you do it.
Please be aware that when installing vanilla mods in Forge, you'll likely overwrite some of Forge's functionality. This could cause mod conflicts and crashes that would usually not appear in a healthy Forge installation.
How do I find my .minecraft folder?
There are three ways to find the .minecraft folder:
Method 1: Via resource packs menu
Method 2: Finding it manually
On Windows: Press Windows+R, type the following:
and press Enter.
On Mac: Navigate to ~/Library/Application Support/minecraft. This is your .minecraft folder.
On Linux: Navigate to ~/.minecraft. This is your .minecraft folder.
Method 3: Using the launcher (recommended!)
Can I use another folder than .minecraft for my game data?
Absolutely! If you want to put your game files in another folder, then, in the Minecraft launcher, click on the Edit profile button in the bottom left corner. Check the box next to "Game Directory" and insert the full path to where you want your game files (mods, saves, screenshots, resource packs etc.) stored. Click on Save Profile when you're done.
Note: You may have to move your existing "saves", "mods", "screenshots", "resourcepacks" and other relevant folders from .minecraft to the new directory you've chosen if you have already played with .minecraft as your game directory previously.
Forums user Botjoe helpfully informs that using multiple different game profiles with different game directories can be very useful if you like to switch between multiple versions of modded Minecraft, or different collections of mods. For instance, having one game directory called something like "FTBInfinity" and another called "The1.7.10Pack" for each of those modpacks will stop you from accidentally loading the wrong world in the wrong modpack, corrupting the world. If multiple players play on the same computer, changing game directories can also be useful to ensure that the players do not play on each other's worlds by accident.
Important: What should I watch out for when I download mods?
There are a lot of traps that are easy to end up caught in when downloading mods:
Also beware of which sites you download mods from. Always download from the official download page. The sites listed below are well-known mod hosting or linking sites which can be trusted, except if the above criteria make you worry (i.e. executable files have been seen on these forums, although very rarely, and in those cases, be extra careful).
http://www.minecraftforum.net/
http://www.planetminecraft.com/
http://minecraft.curseforge.com/
https://mods.io/
http://bot.notenoughmods.com/
http://modlist.mcf.li/
http://www.curse.com/mc-mods/minecraft
If the mod's official topic or page links to another domain for downloading, chances are that it's safe to download.
If the site you are downloading from is on this list (link) , do not download. The sites listed there are known for stealing mods from the original authors and may even be infected with malware and viruses.
Will mods work even if they're not made for my Minecraft version?
The simple answer is no. The reason why is because Minecraft's source code is encoded. Minecraft is encoded through obfuscation; that is changing human readable names of things into seemingly random series of letters, like "Minecraft" may be changed to "azd" and "GuiNewChat" into "bav". In mods' raw source code, there are references to these obfuscated names. The problem is that these names change over time - there are new names for everything with every new release.
If the mod source code references "bav", it would correctly reference "GuiNewChat" (the chat window) in the Minecraft version it's designed for. However, because the obfuscation pattern changes between each release, in another Minecraft version it might reference "GuiButton" instead (Minecraft buttons). This causes problems because the mod's source code doesn't automatically detect that it's referencing the wrong thing.
If you frequently play different Minecraft versions, it's recommended that you separate their game directories so that you do not accidentally load the wrong Minecraft world into a different version of the game.
What is MCP, and why is it so important?
MCP is short for Mod Coder Pack. What this does is help mod developers develop mods for Minecraft easily. If you look at the question above this, you'll see that the Minecraft source code is obfuscated. Developing mods without MCP isn't impossible, rather very difficult, and few want to do that work. What MCP does is that it acts like a translator, translating the meaningless, obfuscated names in the source code and turns them into names modders can understand.
MCP is also the tool that decompiles Minecraft. In terms of software, decompiling is reverse engineering - it is turning the actual program back into source code form. Modding compiled code directly is probably the toughest form of programming there is - compiled Java code is called bytecode, and bytecode is simply a long series of bytes. An example of bytes could be "�ˣ�#M6u�" - now that isn't proper Java bytecode, but is what one could expect from looking at raw class files if opened in Notepad. Being able to understand that and edit it is a huge feat in itself. MCP also does the work of recompiling the decompiled source code back to bytecode form, so Java can understand it.
MCP is written in Python, and is being developed by Searge, ProfMobius, IngisKahn, Fesh0r, ZeuX and R4wk. The community also contributes mappings from obfuscated names to human readable names for MCP. Their official website is http://mcp.ocean-labs.de/.
Why can't mod authors avoid using the Mod Coder Pack and Forge, to update faster?
Originally posted by bilde2910 here.
Modding without MCP, Forge, etc. is, to put it short, extremely difficult. Mainly because the Minecraft source is encoded, and while you can mod in this encoded source, few want to put forth any effort to try doing so. Minecraft is encoded through obfuscation; that is changing human readable names of things into seemingly random series of letters, like "Minecraft" may be changed to "azd" and "GuiNewChat" into "bao". You may be thinking that it shouldn't be too difficult to learn these names, or at least the most important ones, and indeed, I pulled those two names of the top of my head simply because I've worked a lot of them. If I want to access the Minecraft data directory (.minecraft), I know I should look for "azd.w," which translates to "Minecraft.mcDataDir".
Learning a few is easy enough. Learning many (like, how to render text on screen, adding textures to blocks, making interactive GUIs, etc.) is a whole other story. De-obfuscating the source code is like translating a text from one language to another. Learning some words is easy, learning many is hard. And this is where MCP comes in. MCP is short for Mod Coder Pack, and functions much the same way as an automated translator. It de-obfuscates everything for you, and as an added bonus; from 1.7.2 and on it also categorizes the code for you, based on what purpose each code file serves. To use a metaphor for this, I could say that it picks up a pile of 1000+ Latin documents from the floor, translates everything to English before sorting it similarly to like in an archive. This lets you have something that translates Latin to English, so you can work on it, and then back again to Latin when you're done, instead if you having to learn Latin to perform corrections in the documents.
There's also another, very good reason to not learn the obfuscated language yourself. Between the Minecraft versions, the obfuscation changes, so you'll have to learn what everything does all over again. If the new pile of documents is in Afrikaans, I doubt you'd want to learn that new language when you know you're going to get your hands on a translator to do the job for you in not too long time.
If you wonder where Forge comes in play, I'm coming to that now. Forge is a so-called API. API stands for Application Programming Interface, and as you may guess from its name, it's used to make programming easier by providing a set of functions to take use of. One such function would be adding a block, or a dimension, or a mob to the game. It allows the mod to add things in a very easy way and with much less messy code than it would have to if it was to add blocks without Forge. It also allows putting all the code for adding things into a single class file, meaning it is easier for the developer to keep track of what he's doing. In vanilla Minecraft, not only would he need to use multiple files, he also needs to keep track of which class files he's modifying.
Another very neat function of Forge is that it lets you use many (up to hundreds) of mods at the same time without either one conflicting with each other. If you had several block adding vanilla mods, they all probably would need to edit the block registry file. As the code of multiple mods can't easily be merged together, only one mod would work and most likely the game would also crash. Finally, there's another reason to use Forge above vanilla mods. There used to be plenty of vanilla mods up until Minecraft 1.6. From there on, the game required a whole new launcher to play properly, and this launcher introduced a new way of keeping track of the Minecraft versions. Installing mods was no longer as straight forward as putting the class files in a jar file and deleting a folder. Now, you had to make copies of the Minecraft version you needed, actually change something in a code file and add a new profile to the launcher. Forge mods still just have to be dropped into the mods folder in .minecraft.
How do I solve ID conflicts in Forge 1.6.4 (or earlier) mods?
Originally posted by MCforfreeuser here and modified to fix some mistakes.
After installing a new mod, you might have some ID conflict. Your added block might do something different or crash when you interact with it. It may also crash directly at the Mojang screen. You might even see a mob doing something another mob should've done (this is rare, and when it happens you rarely can fix it). All these types of behavior are caused by ID conflicts.
Everything in the world of Minecraft has an ID. Blocks have, items have, entities have too. At the Mojang screen, Forge creates a list of those IDs from the game and the mods. If two things have the same ID, Forge will crash because it doesn't know what to do. If it is an item ID conflict, Forge simply overwrites the block. If it is a block ID conflict, it crashes at the Mojang screen. If it is an entity ID conflict, Forge overwrites the mob.
You can scan for ID conflict by opening the log file which name is 'ForgeModLoader-client-0.log', located in the .minecraft folder. You can open it using Notepad, or another text editor. Then, use the find function by pressing Ctrl+F. Fill the 'Find' box with 'conflict'. Do the search. You may find some. It will look like this:
You can see that Forge overwrites the blocks. If they were items, you would find a crash report after the above lines.
To fix it, go to 'config' folder and find the questioned mod's config file. Look for the numbers above (in this case, 1269). Change it to something else. However, the ID lists have limits - if you put an ID outside the limit, the game crashes. Block ID limit is 128-4095, item ID limit is 128-65535. Also, ensure you don't choose any ID listed on this Minecraft Wiki page, as those are reserved by the game itself (things like gold ore, enchanting table, dirt, etc.). After you change the number, save and exit the config. Run the game again. If it still conflicts, repeat the process.
Mods should start using IDs from 256 and higher, to prevent problems with Minecraft itself. Mods for Minecraft 1.7 and above do not typically suffer from ID conflict issues.
What are IDs, and what are they used for?
In Minecraft terms, IDs are unique numbers or letters used by the game to identify blocks, items, mobs, dimensions and other things. Think of them as barcodes on cardboard boxes: All the boxes look the same, but whatever is inside them varies. So how would you know what's inside? You could place barcodes on the boxes. Scan the barcode, and you'll know what's inside the box. That's pretty much exactly what Minecraft does. The game finds what seems to be some kind of block, and then it scans its ID and figures out that "hey, that's a grass block".
IDs in Minecraft consist of numbers and letters. From Minecraft was released in 2009, the game used numbers to keep track of what things were. Everything from 0-255 was a block, everything from 256-65535 was an item. Dimensions had their own system, 0 representing the overworld, -1 the Nether, and 1 the End. Monsters and animals shared their own system too. This system was used until the release of Minecraft 1.7. From that version and on, blocks and items weren't referred to by numbers, but by actual names. Gold ore, for instance, used to have the ID '14', but this was changed to 'minecraft:gold_ore'. Air, which counts as a block, used to have the ID '0', but this was changed to 'minecraft:air'. Not only did this make it easier for people to remember the IDs of things, it also made it possible to install mods without having the notorious ID conflicts.
The mod I installed crashes my game! What should I do?
What to do in this case depends on what kind of mod that's crashing. If we're speaking of a Forge mod, then first of all ensure there are no ID conflicts. You can identify ID conflicts and fix them by looking in the solving ID conflicts section. If it's a vanilla mod (one you install straight into the Minecraft jar, ensure you've deleted the META-INF folder in the jar file and that you carefully followed the instructions in the installing vanilla mods section. If you're confident that you've done it right, then check the following:
If you're sure about this too, you should report the crash to the mod developer. For more information on how to submit a useful crash report, please see the next section. Remember that there is no way a mod developer can fix a bug if there is no one around to tell him that said bug even exists at all.
How do I report a crash in a useful way?
If your game crashes, you'll be returned to the Minecraft launcher. There should be a crash report visible in it. One important thing to remember is to include this in your post. Posting this in plain text on your post will take up a lot of space, so it is highly recommended that you wrap it in spoiler tags. How, you ask? Well, in your forum post, follow this template:
This will display a small rectangular bar with a Show button above, so people can check out your crash without it covering the entire page automatically.
If there, for some reason, are no crash reports, go to the Developer Console tab of the launcher and paste that in instead.
Another thing you should (must) post is what triggered the crash. What were you doing prior to the crash? Did you craft a block using red sand and compressed iron ore on a green crafting table, and after that, you placed it on the ground and broke it with an obsidian pickaxe? If so, then say so. There are often several ways for a specific thing to happen, but there may well be only one specific scenario where a crash occurs. The developer will figure out if it only happens with the procedure you gave him, or if it's a generic crash that happens with, say, any kind of pickaxe.
When the developer responds: If he is asking of you more information, then give him that information. Don't just tell him that "no it just doesn't work pls fix!!!!" because that won't help him at all. I don't have time to explain everything a developer needs to fix a bug, but if you're interested, I'd highly suggest giving this page a read-through: http://www.chiark.gr...atham/bugs.html
How do I downgrade Minecraft?
In the Minecraft Launcher, look in the bottom left for the profile selector. Press New Profile. Name the profile to something understandable (like, "1.6.4"). Then, select the preferred Minecraft version from the Minecraft Version dropdown. Save the profile. Whenever you want to play this version, simply select the version from the profile selector and hit Play.
Warning: Do not play worlds you created in a newer version of Minecraft when you play an old version. Doing this will cause serious problems and may result in unfixable damage to your entire map. This will cause you to permanently lose all your work. Playing newer Minecraft version maps in older versions of Minecraft may also cause the game to crash. If you frequently play different versions of Minecraft, consider setting up different profiles in the launcher that use different game directories, so that the worlds from one version cannot be accidentally loaded into another version of the game.
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
And a good rule of thumb is that if a mod has been vetted here on the forums - As in actually downloaded and tested and commented on by forum-goers, it's most likely safe. Some of the third-party mod sites may make it look like a mod has been vetted, but often times the creator of the virus just logs in with multiple accounts to comment on his own 'mod'. That's a lot harder to do here on this forum where everyone watches out for everyone's back.
Thank you for kind and uplifting words
You have some good ideas - I'll do some research into how ID conflicts are solved, common configuration formats and common types of crashes, how to report crashes etc. It will probably take a while, but maybe tomorrow or in a few days I may have this done.
You have a good point, too - I'll make sure to add your considerations to the main post as soon as I have enough time to formulate it in a nice way. As for the links, I'll fix that right away as that is a serious security problem and should be fixed as soon as possible.
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Thank you I was hoping it would prove to be useful!
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Also, if you feel you could contribute to this post, please reply, I'd highly appreciate!
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
Solving ID conflicts:
Using Forge
Requirement:
Comprehension of the above guide
A played Minecraft+Forge version
Usually, you can configure mods. The config is saved in 'config' folder inside '.minecraft'.
After installing a new mod, you might have some ID conflict. Your added block might do something different or crash when you interact with it. It may also crash directly at the Mojang screen. You might even see a mob doing something another mob should've done(this is rare, and when it happens you rarely can fix it). All this are caused by ID conflicts.
Everything in the world of Minecraft has an ID. Blocks have, items have, entities have too. At the Mojang screen, Forge creates a list of those IDs from the game and the mods. If two thing have the same ID, Forge will error because it don't know what to do. If it is a block ID conflict, Forge simply overwrites the block. If it is an item ID conflict, it crashes at the Mojang screen. If it is an entity ID conflict, Forge overwrites the mob.
You can scan for ID conflict by opening the log file which name is 'ForgeModLoader-client-0.log'. You can open it using Notepad. Then, use the find function by pressing Ctrl+F. Fill the 'Find' box with 'conflict'. Do the search. You may find some. It will look like this:
You can see that Forge overwrites the blocks. If it was items, you would find a crash report after the above lines.
To fix it, go to 'config' folder and find the questioned mod's config file. Look for the numbers above(in this case, 1269). Change it to something else. However, the ID list have a limit. If you put an ID outside the limit, the game crashes. Block ID limit is 256-4095(4096?), item ID limit is 256-65536. After you change the number, save and exit the config. Run the game again. If it still conflicts, repeat the process.
Using Vanilla Mods:
That's all I can type. Good guide!
OcD Simple Add-On!
Thank you so much for your valuable contribution! I reworded it a little, fixed some typos, and added it to the main post. I didn't add the vanilla instructions, seeing as one can only have one block adding vanilla mod installed at a time without crashing, because all of them would have to override the block registry in some way or the other.
+ Added info on resolving ID conflicts in Forge
+ Added info on what IDs actually are
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
One more. Block ID limit is 128-4095, so it is possible to have a block which ID is 4095. So this:
is not true.
Can you also add a note? [Air is actually a block and its block ID is 0.]
OcD Simple Add-On!
Added. Thanks again However, one thing to note; vanilla uses block IDs from 0 to 175 currently. It also uses item IDs 256 through 422 and 2256 to 2267. Should I possibly include that in the main post?
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
It's up to you, but I think you should. More knowledge for the people, y'know.
OcD Simple Add-On!
Sorry for not being here earlier, but I've been busy with the copyright thread and school work. Will make sure to link to the wiki page on data values as soon as I'm on my laptop, because posting and editing on an iPad is bordering to the impossible due to some JavaScript ruining everything.
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
OcD Simple Add-On!
I don't know what Guff says, but I'm by all means for copyright and have proven people wrong a few times there. However, I'd like to keep that discussion out of this topic.
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
You have to use your jetpack! WOOSH!
I added in a link to it! (Finally... :3)
I also added some information on how to report crashes in a way mod developers can understand.
Thank you :')
I AM NOT YOUR PERSONAL MINECRAFT MOD SUPPORT AGENT, SO PLEASE DO NOT PM ME ABOUT PROBLEMATIC MODS THAT ARE NOT MINE. If you're having trouble/crashes with a mod, you'll have better luck resolving it in this forum section than PMing me. If you already made a topic, be patient about responses. If you have troubles with anything non-Minecraft related on your PC, I might be able to help, though, but no promises. Even though I could wish to be, I'm not a wizard.
OcD Simple Add-On!
This is an issue I've never heard about(or maybe not)... Do you mind getting newer version of Forge? This may not a problem with mods, so I can barely help. And, by logs I meant ForgeModLoader-client logs which appear on your .minecraft folder. Sorry for the confusion, but that piece of log shows nothing about errors. Can you get that one? Open it, press Ctrl+A, copy it, and paste it in Pastebin. Thank you for your acknowledgement in this guide!
bilde, can you add some basic BBCode tutorial on the front post?
OcD Simple Add-On!