Minecraft Version

1.21.5

Mod Loader

NeoForge

Describe the Issue

When I upgrade my client and server to the latest Balm, the server runs fine but I get this error when attempting to connect to it:

[31Mar2025 13:36:13.220] [Render thread/WARN][net.minecraft.client.multiplayer.ClientCommonPacketListenerImpl/]: Client disconnected with reason: Internal Exception: io.netty.handler.codec.EncoderException: Failed to encode packet 'clientbound/minecraft:custom_payload'

This issue goes away when I downgrade the client and server mod back to balm-neoforge-1.21.5-21.5.5.jar

Logs

minecraft-client-log-from-curseforge-2025-03-31.txt

In case it helps, you'll see the client mods in the attached, but the only ones I'm using on the server are (aside from Balm):

• dungeons-and-taverns-v4.7
• Explorify v1.6.2 f10-48
• journeymap-neoforge-1.21.5-6.0.0-beta.43
• lithium-neoforge-0.16.0+mc1.21.5
• waystones-neoforge-1.21.5-21.5.1

And I believe it is only Waystones that requires Balm from that list (but not 100% on that).

Should be fixed in 21.5.10

I can confirm I no longer have this issue with 21.5.10.

Thanks for turning this around so fast (and for all the work you do on this in the first place)!