Quote Originally Posted by VBAhack View Post
...Any idea what could cause this? Scary stuff....
If you still have a copy of the bad workbook, try opening it and go to the VBA IDE. Open the Project Explorer window and look for duplicate Worksheet Names. Several years ago I had a project that would go crazy and the file size would start doubling. It would be storing phantom worksheet copies (same friendly name) that could only be found via the Project Explorer. I never tried your solution though and always ended up copying the good sheets to a new workbook.