shutting down excel

I have used Excel 2007 for about a year, recently I have noticed this condition: When I open excel to an excel file I have used many times make changes or not I close the file by clicking the X in the upper right corner OR file/exit a blank Excel screen comes up with a warning note that Excel closed wrong and windows is searching for the cause it never finds anything but a blank Escel comes up to create a new file, I must close it with no warnings that it was closed incorrectly.

Any Ideas for what is causing this??

How big is the file?

Does it contain DDE links?

Does it contain macros?

What Windows service pack are you running? (IE, is it up-to-date?)

Anyway... in 2003...
Help > Detect and Repair
Try this. Did it fix stuff? (May need install disc).