Server log 1/26/14

2014-01-26 19:00:36 [INFO] Starting minecraft server version 1.6.4
2014-01-26 19:01:06 [INFO] Loading properties
2014-01-26 19:01:06 [INFO] Default game type: SURVIVAL
2014-01-26 19:01:06 [INFO] Generating keypair
2014-01-26 19:01:06 [INFO] Starting Minecraft server on *:25565
2014-01-26 19:01:18 [INFO] Preparing level "DW20World"
2014-01-26 19:01:20 [SEVERE] Chunk file at -9,3 is in the wrong location; relocating. (Expected -9, 3, got -5, 8)
2014-01-26 19:01:20 [INFO] Preparing start region for level 0
2014-01-26 19:01:21 [INFO] Preparing spawn area: 43%
2014-01-26 19:01:22 [INFO] Done (3.261s)! For help, type "help" or "?"
2014-01-26 19:01:25 [WARNING] Can't keep up! Did the system time change, or is the server overloaded?
2014-01-26 19:01:25 [SEVERE] Encountered an unexpected exception ReportedException
net.minecraft.util.ReportedException: Exception ticking world

	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:663)

	at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:276)

	at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:587)

	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:484)

	at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:583)

Caused by: java.lang.NullPointerException

	at net.minecraft.world.gen.ChunkProviderServer.func_73156_b(ChunkProviderServer.java:328)

	at net.minecraft.world.WorldServer.func_72835_b(WorldServer.java:181)

	at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:657)

	... 4 more

2014-01-26 19:01:25 [SEVERE] This crash report has been saved to: C:\Users\Matt\Dropbox\Minecraft\DW20 1.0.12\.\crash-reports\crash-2014-01-26_19.01.25-server.txt