Excel 2010 corrupts files when the user chooses 'print and preview' with a wide variety of printers. Once this happens, all work since the last save is lost. This issue is discussed by users and Microsoft engineers at http://answers.microsoft.com. The specific link is http://answers.microsoft.com/en-us/o...cfa9190?page=1 . In my case, if I choose Microsoft One Note as the default printer, this does not happen.

Microsoft's responses have not satisfied anyone on that forum.