Minecraft Forums

My friend and I play on an unmodded minecraft client in one world that we open to lan with each other and have been playing for months now. We have a lot of project finished and still in the works but unfortunately whenever I try to open the world, it will enter the loading screen and then immediately revert to the main menu. But it's not only this world that has this problem. The same thing happens when I try to enter different worlds or create a new one. Once i was able to create and new one but i just floated in ungenerated space.
I've tried the force update, deleting the bin folder, deleting everything but the saves folder in .minecraft, and I am current updating my nVidia driver. This only started since 1.5 and 1.5.1 . Any ideas on how to fix this?


Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem; Sending packet


---- Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 3/25/13 2:09 PM
Description: Sending packet

java.lang.NullPointerException
at ch.b(SourceFile:107)
at ch.a(SourceFile:39)
at jh.b(SourceFile:430)
at gu.b(SourceFile:669)
at gu.a(SourceFile:79)
at bjk.b(SourceFile:73)
at net.minecraft.server.MinecraftServer.r(SourceFile:480)
at net.minecraft.server.MinecraftServer.q(SourceFile:397)
at bjh.q(SourceFile:122)
at net.minecraft.server.MinecraftServer.run(SourceFile:331)
at gp.run(SourceFile:573)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at ch.b(SourceFile:107)
at ch.a(SourceFile:39)

-- Packet being sent --
Details:
Packet ID: 4
Packet class: fh
Stacktrace:
at jh.b(SourceFile:430)
at gu.b(SourceFile:669)
at gu.a(SourceFile:79)
at bjk.b(SourceFile:73)
at net.minecraft.server.MinecraftServer.r(SourceFile:480)
at net.minecraft.server.MinecraftServer.q(SourceFile:397)
at bjh.q(SourceFile:122)
at net.minecraft.server.MinecraftServer.run(SourceFile:331)
at gp.run(SourceFile:573)

-- System Details --
Details:
Minecraft Version: 1.5.1
Operating System: Windows Vista (amd64) version 6.0
Java Version: 1.7.0_17, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1126876208 bytes (1074 MB) / 2058027008 bytes (1962 MB) up to 2058027008 bytes (1962 MB)
JVM Flags: 2 total; -Xmx2048m -Xms2048m
AABB Pool Size: 113708 (6367648 bytes; 6 MB) allocated, 113708 (6367648 bytes; 6 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 1, tallocated: 63
Profiler Position: N/A (disabled)
Vec3 Pool Size: 11358 (636048 bytes; 0 MB) allocated, 11358 (636048 bytes; 0 MB) used
Player Count: 0 / 8; []
Type: Integrated Server (map_client.txt)
Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.

Thanks for the welcome!

I tried what you suggested but the same crash to main menu still occurs :/

This same thing has been happening to me since updating to 1.5...

I've updated Java, re-installed minecraft, used old saves and new worlds and forced update. Old world doesn't get past downloading packages and new world plays (really slow) until it too crashes after about 1 minute, always the same message as above.

Any help muchly appreciated!

Oh, and playing offline too!

Fixed it..... Sort of.... Lost 50hrs ish of my world but better than starting fresh.

If you don't have a saved file (that works), you won't have anything left unless there is another way around it.

http://www.gamefaqs.com/boards/606524-minecraft/65670267/737445404

Open up Minecraft folder in user\appdata

In Region, delete the newest file and replace it with an old save version. if you dont have an old save, just delete it and it will load a new one but most (if not all) of your world is gone, depending on your saves and game.

Good Luck

This once happened to me, but I had mods. I deleted a mod that was causing this and it worked perfectly.