Pikarack

So i might need some help. every time i add either too many items or not enough items version 1.7.10 to my server it keeps crashing . any idea why? Description: Exception in server tick loop java.lang.NoClassDefFoundError: net/minecraft/client/Minecraft at TMIConfig.isMultiplayer(TMIConfig.java:87) at TMIForgeContainer.playerInteract(TMIForgeContainer.java:48) at cpw.mods.fml.common.eventhandler.ASMEventHandler_1_TMIForgeContainer_playerInteract_PlayerInteractEvent.invoke(.dynamic) at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54) at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:140) at net.minecraftforge.event.ForgeEventFactory.onPlayerInteract(ForgeEventFactory.java:100) at net.minecraft.server.management.ItemInWorldManager.func_73078_a(ItemInWorldManager.java:353) at net.minecraft.network.NetHandlerPlayServer.func_147346_a(NetHandlerPlayServer.java:556) at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:60) at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:9) at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212) at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165) at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659) at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:334) at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547) at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427) at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) Caused by: java.lang.ClassNotFoundException: net.minecraft.client.Minecraft at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ... 17 more Caused by: java.lang.RuntimeException: Attempted to load class bao for invalid side SERVER at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:50) at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279) at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176) ... 19 more