Minecraft Forums

I haven't been able to fix it, but I think I know what the problem is: We got new internet shortly before the issue started happening. So, I believe that something in this new internet (a firewall, I think) is preventing the two computer from communicating with each other. We can both get on servers hosted at a different wifi network, but not LAN servers. Or, servers that I've hosted myself. As long as we're on the same wifi, we can't even make servers to connect to. I can't figure out how to allow the two computers through the internet's firewall. I've tried typing in my IP address in the web-page bar, fiddling with the firewall there, and nothing. So, I don't think it's something with the computers, just something with our new internet.

really strange.. i have not faced something like this before.. i am very sorry but this is my limit, i cant help anymore but if you rage to death you can Format both laptops

You could also check your antivirus software to make sure it isn't blocking the connection. We also just helped another with a similar issue and it turned out to be that they were behind a VPN.

Here is that Port forwarding topic that you may be able to get insight from with videos for creating both Vanilla and Forge servers; as well as; a video on port forwarding.

Quote from OcAMD»

You could also check your antivirus software to make sure it isn't blocking the connection. We also just helped another with a similar issue and it turned out to be that they were behind a VPN.

Here is that Port forwarding topic that you may be able to get insight from with videos for creating both Vanilla and Forge servers; as well as; a video on port forwarding.

I've tried port forwarding, same error. I'm pretty sure it's something with our new internet. It worked perfectly the day before we got it.

Quote from mjbmitch»

Can you ping your brother's computer via command line?

Yes.

Just curious if something like this would help you. It is a server wrapper so you could host a home server. You would just create a new folder and place your server.jar in that folder (If you are modded use the same Forge jar and install server in the new folder). Then run the wrapper exe from that folder. This is an alternate to the first that includes a port forwarding tab. I actually run better like this than with LAN and people don't have to be on the same network and allows more control.

have you tried direct connect again?

download the minecraft server jar from http://minecraft.net/download. After you downloaded the server jar, put the jar in a folder. Then right click inside the folder and click new text document. After this open the text document and type "java -Xmx1024M -Xms1024M -jar minecraft_server.1.8.7.jar nogui." (without quotes). After that under the file tab in notepad, click "Save as" and where is says file type select "all". Then save the file as "start.bat" (without quotes". Then run start.bat. Then your brother can connect using your local ip.

Quote from TNT123BOOM»

have you tried direct connect again?

Yes, same error.

Some WiFi Routers can be configured to prevent WiFi client from talking to anything except the WAN port (i.e. the Internet).

This is a security feature, e.g. you let your guests use WiFi surf the internet, but you don't want them connecting to your NAS or your printer or your desktop.

If this is your problem how to fix it would depend upon what device you have.

Quote from Afootpluto»

download the minecraft server jar from http://minecraft.net/download. After you downloaded the server jar, put the jar in a folder. Then right click inside the folder and click new text document. After this open the text document and type "java -Xmx1024M -Xms1024M -jar minecraft_server.1.8.7.jar nogui." (without quotes). After that under the file tab in notepad, click "Save as" and where is says file type select "all". Then save the file as "start.bat" (without quotes". Then run start.bat. Then your brother can connect using your local ip.

How would I do that for a modded server?

Quote from gerbil»

Some WiFi Routers can be configured to prevent WiFi client from talking to anything except the WAN port (i.e. the Internet).

This is a security feature, e.g. you let your guests use WiFi surf the internet, but you don't want them connecting to your NAS or your printer or your desktop.

If this is your problem how to fix it would depend upon what device you have.

That is the issue exactly. We use Comcast's newest modem for internet. (I forgot what it's called.)

My instructions above; you just use the Forge jar that you used to install it to run mods. It has an install server option.

This is the actual arguments for my batch that I had to use to stop the server can't keep up tick warnings for mine.

java -Xms2048M -Xmx2048M -native -server -d64 -XX:ParallelGCThreads=4 -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSIncrementalPacing -XX:+AggressiveOpts -XX:+CMSParallelRemarkEnabled -XX:+DisableExplicitGC -XX:MaxGCPauseMillis=500 -XX:SurvivorRatio=16 -XX:TargetSurvivorRatio=90 -XX:+UseAdaptiveGCBoundary -XX:-UseGCOverheadLimit -XX:UseSSE=3 -XX:MetaspaceSize=128m -XX:LargePageSizeInBytes=4m -jar forge-1.8-11.14.1.1371-universal.jar -o true nogui
PAUSE

If you need info or break down documention I'll be happy to link for you.

This is where you install the Forge server from.

Quote from MinecraftLover9001»

That is the issue exactly. We use Comcast's newest modem for internet. (I forgot what it's called.)

You should be able to call their tech support and get them to help you disable it then or research the model number for information on the internet.

Or post it here. But I can tell you that you should not be using the wifi network "xfinitywifi" if you have it.

That's the one that any comcast customer can use and therefore doesn't allow wifi client to wifi client (or wired client) communications.

It's basically a semi-public hotspot for random comcast customers.

If you have an Arris device, the feature that keeps WiFi clients separate is called "AP Isolation"

Quote from gerbil»

Or post it here. But I can tell you that you should not be using the wifi network "xfinitywifi" if you have it.

That's the one that any comcast customer can use and therefore doesn't allow wifi client to wifi client (or wired client) communications.

It's basically a semi-public hotspot for random comcast customers.

If you have an Arris device, the feature that keeps WiFi clients separate is called "AP Isolation"

Neither of us use the "xfinitywifi" hotspots, we use our actual home internet, and our router is ASUS, but it worked fine before.

Ok, I actually fixed the issue this time. The issue was that the wifi was set to a public network for some reason, but upon switching it to a private network like it used to be, we could connect. Thanks to everyone who tried to help, though!

Quote from MinecraftLover9001»

Ok, I actually fixed the issue this time. The issue was that the wifi was set to a public network for some reason, but upon switching it to a private network like it used to be, we could connect. Thanks to everyone who tried to help, though!

I suggested that fix in comment #16 but you said you already checked that; but thanks for reporting back and I'm glad you got it fixed.