I am playing Minecraft on Ubuntu, running it with the following command (in a bash file)
padsp java -Xms1024M -Xmx1024M -Djava.net.preferIPv4Stack=true -jar /home/lagerdalek/Games/Minecraft/Minecraft.jar
Over the last 4 weeks I have lost 5 worlds.
This is not the problem where a world is no longer visible from the menu, and I need to rename level.dat; rather, it is visible as a save game, but when I open it, it is a new, freshly generated world! Once it was the chunk I had saved with all other chunks deleted, but otherwise it is new.
Minecraft had not crashed, rather I had saved the game and exited by closing the window.
This is getting very annoying. If anyone else is suffering from this problem, have you found a work around? Should I back up saves after I finish a game or is it too late by then?
Best Answer
One work around is to run your own Minecraft server. The a dis-advantage this the Nether isn't currently working. You can launch the Minecraft server to load single player worlds. Just find your old ./world# folder in your .minecraft directory. When launching the server be sure your world matches the world name in the server.properties file.
I believe Mojang mentioned going this route in the future with Single player. Having the client launch a server instance locally and connect to it.
When this is fixed in future versions it should be a simple copy of the ./world folder back to your .minecraft directory and you will be able to load the world normally again.