Hello guys , my server crashes about every 30-60 mins and i dont know why Code: java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:894) at java.util.HashMap$KeyIterator.next(HashMap.java:928) at net.minecraft.server.v1_4_6.EntityTracker.a(EntityTracker.java:191) at net.minecraft.server.v1_4_6.EntityPlayer.j_(EntityPlayer.java:186) at net.minecraft.server.v1_4_6.World.entityJoinedWorld(World.java:1334) at net.minecraft.server.v1_4_6.WorldServer.entityJoinedWorld(WorldServer.java:548) at net.minecraft.server.v1_4_6.World.playerJoinedWorld(World.java:1315) at net.minecraft.server.v1_4_6.World.tickEntities(World.java:1193) at net.minecraft.server.v1_4_6.WorldServer.tickEntities(WorldServer.java:445) at net.minecraft.server.v1_4_6.MinecraftServer.r(MinecraftServer.java:580) at net.minecraft.server.v1_4_6.DedicatedServer.r(DedicatedServer.java:224) at net.minecraft.server.v1_4_6.MinecraftServer.q(MinecraftServer.java:494) at net.minecraft.server.v1_4_6.MinecraftServer.run(MinecraftServer.java:427) at net.minecraft.server.v1_4_6.ThreadServerApplication.run(SourceFile:849) A detailed walkthrough of the error, its code path and all known details is as follows: --------------------------------------------------------------------------------------- -- Head -- Stacktrace: at java.util.HashMap$HashIterator.nextEntry(HashMap.java:894) at java.util.HashMap$KeyIterator.next(HashMap.java:928) at net.minecraft.server.v1_4_6.EntityTracker.a(EntityTracker.java:191) at net.minecraft.server.v1_4_6.EntityPlayer.j_(EntityPlayer.java:186) at net.minecraft.server.v1_4_6.World.entityJoinedWorld(World.java:1334) at net.minecraft.server.v1_4_6.WorldServer.entityJoinedWorld(WorldServer.java:548) at net.minecraft.server.v1_4_6.World.playerJoinedWorld(World.java:1315) -- Entity being ticked -- Details: Entity Type: null (net.minecraft.server.v1_4_6.EntityPlayer) Entity ID: 85404 Name: Dark Exact location: 1099.04, 70.00, 587.46 Block location: World: (1099,70,587), Chunk: (at 11,4,11 in 68,36; contains blocks 1088,0,576 to 1103,255,591), Region: (2,1; contains chunks 64,32 to 95,63, blocks 1024,0,512 to 1535,255,1023) Momentum: 0.00, -0.08, 0.00 Stacktrace: at net.minecraft.server.v1_4_6.World.tickEntities(World.java:1193) at net.minecraft.server.v1_4_6.WorldServer.tickEntities(WorldServer.java:445)