net.minecraft.server.v1_5_R2.ExceptionWorldConflict: Failed to check session lock, aborting
at net.minecraft.server.v1_5_R2.WorldNBTStorage.checkSession(WorldNBTStorage.java:75)
at net.minecraft.server.v1_5_R2.World.E(World.java:2590)
at net.minecraft.server.v1_5_R2.WorldServer.a(WorldServer.java:779)
at net.minecraft.server.v1_5_R2.WorldServer.save(WorldServer.java:769)
at net.minecraft.server.v1_5_R2.MinecraftServer.saveChunks(MinecraftServer.java:317)
at net.minecraft.server.v1_5_R2.MinecraftServer.q(MinecraftServer.java:480)
at net.minecraft.server.v1_5_R2.MinecraftServer.run(MinecraftServer.java:409)
at net.minecraft.server.v1_5_R2.ThreadServerApplication.run(SourceFile:573)
