Internal Server Error

It will send me a message after I die Like this:
Here is the server LOG:
[21:16:12] [Server thread/INFO]: William_XDD500 died
[21:16:14] [Server thread/WARN]: Failed to handle packet for /192.168.X.X:58702
java.lang.ArrayIndexOutOfBoundsException: -1
at java.util.ArrayList.elementData(Unknown Source) ~[?:1.8.0_25]
at java.util.ArrayList.remove(Unknown Source) ~[?:1.8.0_25]
at net.minecraft.server.v1_7_R1.World.removeEntity(World.java:982) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.PlayerList.moveToWorld(PlayerList.java:417) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.PlayerList.moveToWorld(PlayerList.java:408) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:1138) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at com.bergerkiller.bukkit.common.internal.network.CommonPacketHandler$CommonPlayerConnection.a(CommonPacketHandler.java:250) ~[?:?]
at net.minecraft.server.v1_7_R1.PacketPlayInClientCommand.a(SourceFile:50) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.PacketPlayInClientCommand.handle(SourceFile:8) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:146) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:655) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.2-49-g17d057c-b3018jnks]
[21:16:14] [Server thread/INFO]: William_XDD500 lost connection: Internal server error
[21:16:14] [Server thread/INFO]: William_XDD500 left the game.
If anyone knows I will be thanks!
Btw I'm using BukkitGUI

 

Please help me!

 

Try taking all plugins off of the server, then try to join it again.

 

Although I take all the plugins, it still happen.

 

Try making a ticket with your server host and explain to them. If you host from your computer, try and backup the world and restart the whole minecraft server.

 

What do you mean? Because I'm Taiwanese, I'm not very well at speaking English.
Can you say it easily?

 

I think that @iOnixS is trying to tell you to submit a report to whichever company hosts your server saying that something is wrong. If you run your server from your computer, Onix is saying that you should move the world to a new server.

 

@PixelBeaver Just change the map to other bukkit core?

 

Yes, I believe so.
(Sorry for very late response)