I used the cleanup and it caused all office suite programs to stop launching.
When I tried to run a repair (actually all I was offered was the "change"
button) it said Office was corrupted and must reinstall.

I reinstalled, same problem of installer asserting itself all over again!

Added up, I'm into my 10th hour troubleshooting this, not even considering
the 5-minute Outlook-launching sequences all day long.

"Syche" wrote:

Quoted from http://support.microsoft.com/kb/290301
Note the very last line...
(the emphasis and exclaimations were added by me.)

"When you use Windows Installer CleanUp Utility, you can perform the
following functions:
Select one or more programs that were installed by Windows Installer from
the Windows Installer CleanUp dialog box. To do this, select the programs
that you want in the Installed Products list in the Windows Installer CleanUp
dialog box. After you make this selection, the utility removes only Windows
Installer configuration information that is related to those programs. Remove
all Windows Installer information associated with the selected programs. This
includes the entries for the programs in the Add Or Remove Programs item in
Control Panel. Be aware that only the Installer information for that
particular program is removed, not the files.

WHAT THIS UTILITY DOES NOT DO...