I have recently installed a new modpack onto my server and I have been having an issue getting it started.  After my server host support team has been unable to help me I decided to come here and post the error I am getting to see if you guys can help me.

 

2013-12-13 00:52:18 [sEVERE] [ForgeModLoader] Unable to launch

java.lang.reflect.InvocationTargetException

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:606)

at net.minecraft.launchwrapper.Launch.launch(Launch.java:57)

at net.minecraft.launchwrapper.Launch.main(Launch.java:18)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:606)

at cpw.mods.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:48)

at cpw.mods.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:17)

Caused by: java.lang.NoClassDefFoundError: net/minecraft/potion/PotionHealth

at net.minecraft.potion.Potion.<clinit>(SourceFile:31)

at net.minecraft.potion.PotionHelper.<clinit>(SourceFile:80)

at net.minecraft.item.Item.<clinit>(Item.java:81)

at net.minecraft.block.Block.<clinit>(Block.java:1426)

at net.minecraft.stats.StatList.func_75921_a(StatList.java:185)

at net.minecraft.stats.StatList.<clinit>(StatList.java:96)

at net.minecraft.server.MinecraftServer.main(MinecraftServer.java:1394)

... 12 more

Caused by: java.lang.ClassNotFoundException: net.minecraft.potion.PotionHealth

at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:179)

at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

... 19 more

Caused by: java.lang.ClassCircularityError: poersch/minecraft/core/IClassPatcher

at poersch.minecraft.core.ClassPatcher.transform(ClassPatcher.java:48)

at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:267)

at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:165)

... 21 more

 

Caused by: java.lang.ClassCircularityError: poersch/minecraft/core/IClassPatcher

Something you have installed is editing the Potion class and adding something that doesnt exist. This is not a Forge issue, it's a issue in your mod pack/config.

Okay thanks Lex.  Guess I will just go through adding the mods one at a time until I find the offender