"Installation Files are missing" - Office 2003

[Hank Arnold]

I've run into a situation where my Office 2003 installation runs fine, but I
have the following problems:

1) The icons are now generic

2) If I try to use the Office Update on the web and tell it to check for
updates, it says "unable to check for updates"

3) If I try to uninstall it or re-install it, I get a message "The
installation Source for this product is not available. Verify that it exists
and you can access it."

Any clues as to what to do? Is there a manual uninstall process?

TIA,
Hank