Not sure if this can be regarded as an issue or not but I'll describe the symptoms and will be interested in the comments. I have a 1.2.10 world and have been playing on a server modded with FallingTree using vanilla clients. As 1.2.11 is out, I wanted to upgrade the world so I installed forge 1.2.11 on the server and copied the world over (I maintain a new directory for each version). Upon trying to access the server with a vanilla client, I get a Network Protocol Error and get kicked off. However, if I try to access the server with a vanilla client and allow the server to create a new world, no error. If I use a forge client with the old, no error. It seems to be the specific combination of using an existing world and the vanilla client. For my purposes right now, I'm fine with using Forge clients. It would be nice to be able to use vanilla (since the mod I use doesn't require client modding). Just wondering if this is in any way possible. Note that I tried removing FallingTree just in case and it made no difference. The logs show Time: 2025-12-12 11:54:23
Description: Packet handling error
java.lang.ArrayIndexOutOfBoundsException: Index 18 out of bounds for length 18
at ama.a(SourceFile:114)
at hig.a(SourceFile:665)
at agp.a(SourceFile:54)
at agp.a(SourceFile:12)
at hig.a(SourceFile:2377)
at adm.a(SourceFile:19)
at adm.a(SourceFile:7)
at xl$a.a(SourceFile:55)
at xl.b(SourceFile:38)
at gfj.d(SourceFile:1337)
at gfj.j(SourceFile:966)
at net.minecraft.client.main.Main.main(SourceFile:250)
A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------
-- Head --
Thread: Render thread
Stacktrace:
at ama.a(SourceFile:114)
at hig.a(SourceFile:665)
at agp.a(SourceFile:54)
at agp.a(SourceFile:12)
-- Incoming Packet --
Details:
Type: clientbound/minecraft:bundle
Is Terminal: false
Is Skippable: false
Stacktrace:
at abb.a(SourceFile:41)
at hia.a(SourceFile:146)
at hia.a(SourceFile:125)
at xl$a.a(SourceFile:60)
at xl.b(SourceFile:38)
at gfj.d(SourceFile:1337)
at gfj.j(SourceFile:966)
at net.minecraft.client.main.Main.main(SourceFile:250)
-- Connection --
Details:
Protocol: play
Flow: CLIENTBOUND
Is Local: false
Server type: OTHER
Server brand: forge
-- System Details --
Details:
Minecraft Version: 1.21.11
Minecraft Version ID: 1.21.11
Operating System: Windows 10 (amd64) version 10.0
Java Version: 21.0.7, Microsoft
Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Microsoft
[redacted]
By
Richy_T · Posted 1 hour ago 1 hr