Problem: The only issue is with Excel *.xlsx documents. A friend somehow managed to associate the .xlsx files with Word, so of course it obviously fails to open with Word. All other Excel files... templates, older *.xls files and such open fine by double-clicking on them.

Attempted fixes:
1)I have gone into and set *.xlsx documents to be associated with the Excel program, however the icon doesn't change to the normal Excel 2011 icon (the icon looks like a blank sheet w/ the normal Excel icon in the middle instead of off to the left side)
2)I have run the Office Repair to no avail
3)I have completely uninstalled, then reinstalled the entire Office suite too.
4)Finally, System Restore didn't work

What happens when I try to open an .xlsx doc? The hourglass comes up like it's thinking about it for maybe 2 seconds, then just goes away and nothing happens.

I wish I could say what happened or what changed to cause the problem, but my friend has no idea. By the way, I can open Excel, go to file--open-- and open an .xlsx document that way. Or just drag the file into the opened Excel program and it works fine.

After everything I've tried, I imagine there is just something registered incorrectly in the registry, but am unable to find out what exactly.

Thank you in advance for your time...