Server can't run (because of single player mod?)

[meowxiik]

I've started a server, and after ~5 mins of loading up, it showed this:

[12:40:44] [Server thread/ERROR]: Encountered an unexpected exception
java.lang.NoClassDefFoundError: net/minecraft/client/multiplayer/WorldClient
        at net.minecraft.profiler.Profiler.func_76320_a(Profiler.java:64) ~[qi.class:?]
        at net.minecraft.world.World.func_147465_d(World.java:459) ~[ahb.class:?]
        at net.minecraft.block.BlockDoublePlant.func_149889_c(BlockDoublePlant.java:140) ~[ako.class:?]
        at net.minecraft.world.gen.feature.WorldGenDoublePlant.func_76484_a(SourceFile:28) ~[arm.class:?]
        at net.minecraft.world.biome.BiomeGenPlains.func_76728_a(BiomeGenPlains.java:79) ~[aip.class:?]
        at net.minecraft.world.gen.ChunkProviderGenerate.func_73153_a(ChunkProviderGenerate.java:421) ~[aqz.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.func_73153_a(ChunkProviderServer.java:279) ~[ms.class:?]
        at net.minecraft.world.chunk.Chunk.func_76624_a(Chunk.java:1055) ~[apx.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.originalLoadChunk(ChunkProviderServer.java:190) ~[ms.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.loadChunk(ChunkProviderServer.java:131) ~[ms.class:?]
        at net.minecraft.world.gen.ChunkProviderServer.func_73158_c(ChunkProviderServer.java:101) ~[ms.class:?]
        at net.minecraft.server.MinecraftServer.func_71222_d(MinecraftServer.java:265) ~[MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:235) ~[MinecraftServer.class:?]
        at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:258) ~[lt.class:?]
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387) [MinecraftServer.class:?]
        at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?]
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.multiplayer.WorldClient
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) ~[launchwrapper-1.11.jar:?]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_11]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_11]
        ... 16 more
Caused by: java.lang.RuntimeException: Attempted to load class bjf for invalid side SERVER
        at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:50) ~[server-1.7.10-1231.jar:?]
        at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) ~[launchwrapper-1.11.jar:?]
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ~[launchwrapper-1.11.jar:?]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_11]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_11]
        ... 16 more

I am pretty sure, there is some mod, that is only single player, but I can't figure out, what is that mod.

 

[ajthemacboy]

A google search of some of the lines of code in your error report turn up this:

 

http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/1287252-continue-of-cjb-mod-fml-modloader

 

Are you using any of these mods?

 

Edit: Possibly these mods:

 

Baubles, BattleGear. Also try removing any chickenbones mod (Code chicken core, not enough items, chickenchunks, enderstorage)

Edited December 7, 2014 by ajthemacboy

[plowmanplow]

Please provide the API URL (the URL you paste into the launcher to add the pack) and I'll tell you which mods must be removed.