Server Crash

[dragonrider273]

Can someone please help me my server keeps crashing and I don't Know why.

I am trying to make a modded server for me and my friends, but it keeps crashing.

Here is crash log... So if you know what is going on pls help this is my first time doing this.

---- Minecraft Crash Report ----
// There are four lights!

Time: 1/30/21 12:51 PM
Description: Exception in server tick loop

cpw.mods.fml.common.LoaderException: java.lang.NoClassDefFoundError: net/minecraft/client/entity/EntityClientPlayerMP
    at cpw.mods.fml.common.LoadController.transition(LoadController.java:163)
    at cpw.mods.fml.common.Loader.initializeMods(Loader.java:739)
    at cpw.mods.fml.server.FMLServerHandler.finishServerLoading(FMLServerHandler.java:97)
    at cpw.mods.fml.common.FMLCommonHandler.onServerStarted(FMLCommonHandler.java:319)
    at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:210)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:387)
    at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)
Caused by: java.lang.NoClassDefFoundError: net/minecraft/client/entity/EntityClientPlayerMP
    at DamageIndicatorsMod.server.DIProxy.register(DIProxy.java:11)
    at DamageIndicatorsMod.DIMod.load(DIMod.java:64)
    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 cpw.mods.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:532)
    at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
    at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
    at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
    at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
    at com.google.common.eventbus.EventBus.post(EventBus.java:275)
    at cpw.mods.fml.common.LoadController.sendEventToModContainer(LoadController.java:212)
    at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:190)
    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.EventSubscriber.handleEvent(EventSubscriber.java:74)
    at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
    at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
    at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
    at com.google.common.eventbus.EventBus.post(EventBus.java:275)
    at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:119)
    at cpw.mods.fml.common.Loader.initializeMods(Loader.java:737)
    ... 5 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.entity.EntityClientPlayerMP
    at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 33 more