Minecraft Server Error with Cobblemon in Modpack

[DiamondLuver22]

I'd love any and all help for this issue. I'm trying to use Exaroton to start a small server up for me and my friends. I used the modpack HazardousDaniel's Unlimited 2.0 as the base and added a few extra mods to that modpack, including Cobblemon.

I keep getting this error that disconnects me from the server: "Internal Exception: io.netty.handler.codec.DecoderException: Unknown serializer type 110". I try joining multiple times with both the IP of the server and the Dyn IP. I usually get different Unknown serializer type numbers too (some examples of the ones I've gotten are 98, 100, 101, 110, 115, etc.).

Sometimes, it even lets me load into the world where I can move around for a moment before disconnecting me to these errors. When I take Cobblemon out of the modpack, the server allows me to join just fine, and playing with this modpack with Cobblemon in a singleplayer world also works just fine.

I'd really like to keep Cobblemon in the modpack, but I've tried a couple different potential solutions I've seen online and none have worked for me. If anyone could read through the logs and understand what's happening, I'd appreciate it! Let me know if you need any other info.

Log: https://mclo.gs/wBsSplt

Edited October 22, 2024 by DiamondLuver22

[TileEntity]

Make a test without carryon and or valkyrienskies (backup the world before)

[Ceezee]

I'm having the same issue with Monifactory version 0.9.7
and on Monifactory 0.9.5 with cobblemon

i just want my silly pokemon with super machines

[Ceezee]

Two of my friends and I are having this connection issue running windows 11
two of my friends running windows 10 aren't having this issue
but one of my friends that is running windows 10 is having this same issue
and I'm having no issue connecting on my steam deck with Linux

This issue makes no sense to me honestly

[TileEntity]

I have no idea

[DiamondLuver22]

6 hours ago, TileEntity said:

Make a test without carryon and or valkyrienskies (backup the world before)

Alright, so I tried removing just Carry On, then added Carry On back and removed Valkyrien Skies and other mods related to it, and then I removed both Carry On and all Valkyrien Skies mods (log: https://mclo.gs/bqRBmKP) and still got the same issue with Unknown serializer codes 109, 111, etc. in all instances.

There seems to be some remnant files of Valkyrien Skies in other folders that I didn't remove but, I really feel like the issue is just with Cobblemon. I was willing to get rid of those mods if Cobblemon worked with them but it didn't. I specifically had a version of the server without Cobblemon at first but then added it in and that's when I started getting that error, and when I would remove it from the modpack, everything worked perfectly again. 

5 hours ago, Ceezee said:

Two of my friends and I are having this connection issue running windows 11
two of my friends running windows 10 aren't having this issue
but one of my friends that is running windows 10 is having this same issue
and I'm having no issue connecting on my steam deck with Linux

This issue makes no sense to me honestly

This is really strange honestly. I had my friend try joining the server with the modpack with Cobblemon in it. His computer runs on Windows 10. He was able to join without disconnecting, and everything seems to be fine, he's able to play (log: https://mclo.gs/RkLxaOT). So, it must be something between Cobblemon and Windows 11 not allowing it to run correctly??? At least some of the blame is seemingly on Windows 11. I have no idea of what to do now to fix this issue for myself though, other than I'll try to do a Windows Update to see if that fixes anything for me. This is so weird, but you testing it with your friends that run it on different OS was an interesting step in the right direction.

Anyone please let me know of any other potential solutions. I really want to play on this modpack with Cobblemon, since my friend is able to play with no issues and now it's just me on Windows 11 that isn't allowing it to work.