NEI crashes server but not singleplayer?

[Bry1527]

Hi,
I need help every time i open my inventory (NEI) on my server it crashes saying "internal server error"
and boots me. Now this JUST started happening randomly. Other people on the server aren't having issues. I'm the one running the server and I crash! I have changed any settings so I'm very confused.
It only happens in multiplayer! Single player works perfectly!
I hope someone can help!
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[WARNING] Failed to handle packet for bry1527/71.201.220.212: java.lang.NullPointerException
java.lang.NullPointerException
at codechicken.enderstorage.api.EnderStorageManager.getStorage(EnderStorageManager.java:237)
at codechicken.enderstorage.storage.liquid.TankSynchroniser$PlayerItemTankCache.track(TankSynchroniser.java:170)
at codechicken.enderstorage.storage.liquid.TankSynchroniser$PlayerItemTankCache.handleVisiblityPacket(TankSynchroniser.java:230)
at codechicken.enderstorage.storage.liquid.TankSynchroniser.handleVisiblityPacket(TankSynchroniser.java:267)
at codechicken.enderstorage.internal.EnderStorageSPH.handlePacket(EnderStorageSPH.java:21)
at codechicken.core.PacketCustom$ServerPacketHandler.handle(PacketCustom.java:125)
at codechicken.core.PacketCustom$CustomPacketHandler.onPacketData(PacketCustom.java:74)
at cpw.mods.fml.common.network.NetworkRegistry.handlePacket(NetworkRegistry.java:243)
at cpw.mods.fml.common.network.NetworkRegistry.handleCustomPacket(NetworkRegistry.java:233)
at cpw.mods.fml.common.network.FMLNetworkHandler.handlePacket250Packet(FMLNetworkHandler.java:71)
at iv.a(NetServerHandler.java:1110)
at di.a(SourceFile:59)
at cg.b(TcpConnection.java:458)
at iv.d(NetServerHandler.java:136)
at iw.b(NetworkListenThread.java:57)
at ht.b(SourceFile:30)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:703)
at ho.r(DedicatedServer.java:269)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)
at fy.run(SourceFile:849)