Yeah it says to me that I can't delete it (all of the .jar files, though) and when I tried to install a mod, when I was deleting that folder, it said it can't because it was being used by something, and nothing was up that used minecraft.jar. It gave me an option to 'BREAK OPERATION' but when I clicked on it, nothing happened. Now how am I suppose to get the 'Too Many Items' mod? Please help!