OK, sorry about the misunderstanding.
At this point, all I can suggest is what I suggested above, try running the Office installer and have it repair the Excel installation. If there is something wrong with the registry, that should fix it.
A more drastic approach would be to uninstall and the reinstall it.
Other than that, I really can't suggest anything else.
Martin Fredrickson
Test Engineer
Northrop Grumman
Advanced Systems and Products
San Diego, CA 92128