Sorry in advance, this is hard to describe.
I find that I end up having many files open with the same name, but some don't have the latest drawing modifications.
I often have different files open and switch back and forth between them. The problem is if I have a file called file1, I will regularly save this file. Later when I'm closing windows I'll close file1 and other files but then earlier versions of file1 appear and I start freaking out thinking that I've lost the last 2 hours work!
Why is this happening, and is there a way of preventing it?