I have been working on a drawing for some time and somehow, I have managed to lose it so that both the .dwg file and the .bak file are blank sheets. I had saved the .dwg file several times and I am sure that the loss of files occurred within one or two save backups. Does the save/backup process extend to several levels? Is it possible to delve into the computer to retrieve the files? Both the .dwg and .bak files are visible on the hard disk and I am not sure how I managed to wipe them. Thanks in anticipation, Ken Rock