I have been asked to help with recovering some corrupted .xls files (created with Excel 2000, but viewed with the 2007 version). Excel 2007's repair function did not work; my 2010 version cannot repair them either. I suggested trying to view them with Open Office Calc, but that was a long shot, I admit.
So I think that some kind of commercial Excel file recovery software is the only option. I have no experience of them, so if any of you have used a particular example of this software and found it effective, what do you recommend?