I have Windows 7 ultimate and Office 2010 beta. All of a sudden I can no longer double-click Excel attachments in Outlook or Windows Explorer and have them open. Excel launches but pulls up a blank Excel app. I can open all files from within Excel app just fine.
I have tried repairing and reinstalling office several times with no success. I have even tried the excel.exe /unregserver and /regserver several times...still with no success.
Now the really odd thing is I created a new dummy user account and Excel is working as normal. I can open the same files from Explorer by double-clicking that I could not as my work domain user.