Switched from Vista to Mac April last year. On Visata, in Excel I kept a spreadsheet with all my monthly payment records. Moved the file to my Mac and kept working with it in Pages. Kept it backed up to my Time Machine. Last month I started using MS Office for Mac. Started working with the same file in Mac Excel. Updated all my payment information ~10 days ago. Did a Time Machine backup just before I did an erase and install for SL. Tonight I couldn't find my file on my hard drive, which is weird because I just worked with it about a week ago. Tried to restore from Time Machine. All copies of that file have been erased from Time Machine. In it's place is a file with a similar name but no file extension. This file is in everyone of my backups. Neither pages nor Excel can open it. TextEdit can't open it because it's a "workbook volume." I can do a QuickLook which reveals information from a single payment back in this April. This file used to have information from payments for about the last 5 years. I've still got the file on Visata and will start over with it. But what the hell happened to my file and all my backups? Any insight appreciated.