I put this mod and my server will not start

[SmokeURSS]

net.minecraftforge.fml.common.LoaderExceptionModCrash: Caught exception from extrautils2 (extrautils2)
Caused by: java.lang.NoClassDefFoundError: net/minecraftforge/fml/common/registry/IForgeRegistryEntry
at com.rwtema.extrautils2.backend.entries.XU2Entries.(XU2Entries.java:200)
at com.rwtema.extrautils2.ExtraUtils2.preInit(ExtraUtils2.java:128)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:637)
at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91)
at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150)
at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76)
at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399)
at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71)
at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116)
at com.google.common.eventbus.EventBus.post(EventBus.java:217)
at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:219)
at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:197)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.Subscriber.invokeSubscriberMethod(Subscriber.java:91)
at com.google.common.eventbus.Subscriber$SynchronizedSubscriber.invokeSubscriberMethod(Subscriber.java:150)
at com.google.common.eventbus.Subscriber$1.run(Subscriber.java:76)
at com.google.common.util.concurrent.MoreExecutors$DirectExecutor.execute(MoreExecutors.java:399)
at com.google.common.eventbus.Subscriber.dispatchEvent(Subscriber.java:71)
at com.google.common.eventbus.Dispatcher$PerThreadQueuedDispatcher.dispatch(Dispatcher.java:116)
at com.google.common.eventbus.EventBus.post(EventBus.java:217)
at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:136)
at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:600)
at net.minecraftforge.fml.server.FMLServerHandler.beginServerLoading(FMLServerHandler.java:103)
at net.minecraftforge.fml.common.FMLCommonHandler.onServerStart(FMLCommonHandler.java:337)
at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:169)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:688)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: net.minecraftforge.fml.common.registry.IForgeRegistryEntry
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:223)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 37 more
Caused by: java.lang.NullPointerException
Any help?
The server is running on Magma-761933c-STABLE

[tomodachi94]

@SmokeURSS what version of XU2, Forge, and Minecraft are you using?