3 Hours of Work Disappeared!

Hello,

I solved it just as I was about to post. But I would still like to know why it went wrong, or what caused the problem.

Using Blender 2.73. For about 3 hours, every time I saved my work, it acted like a “SAVE AS” command - the file requester came up and I double-clicked the file to continue. This was odd, but I didn’t think much about it.

After 3 hours of this, saving often, my .blend file was the same as when I started out. The time stamp showed that there were no saves performed for about 3 hours. I searched all of my hard drives to be certain, and there was no other .blend file saved during this time period.

In short, all of my editing and animation work during the previous 3 hours was gone!

The issue got solved when loading, I noticed an option to recover the last session. Fortunately this worked.

However, since I don’t know why this happened, I am concerned that it might happen again.

The only unusual thing I can think of is that before the 3 hour period in question, I had textured my object, and I wanted to double-check that I did it right so that the material was in fact saved, so I started a second instance of Blender to load the .blend file. It looked fine. But I did some work on it there, in the 2nd instance, and then saved over it. But I think I reloaded my default file into instance #1 (to set up my lights, etc) and then I appended the object back into instance #1 from the file I just saved out of instance #2.

So I sort of ping-ponged it back and forth between 2 instances of Blender. Could this have triggered some kind of bug?

So like I said, from then on when I did File>Save, it acted like File>Save As, and evidently did not save the file…

Thanks for any help!