Not sure what happened but…
I decided to add-remove programs for Office XP because it takes up too much space. I wanted to just remove a couple of things like front page and access, but when it looked like it was going to remove everything, I cancelled the remove.
The next time I went to open Outlook, I got a windows installer window:
“The feature you are trying to use is on a network resource that is unavailable”
“Click OK to try again, or enter an alternate path to a folder containing the installation package “MAINSP3ff.msp” in the box below”
I get this same message when I try to add-remove programs or try to reinstall the program from disk. I downloaded the SP3 patch with the MAINSP3ff.msp, but I get a message saying this patch is already installed. When I run search to find it, nothing comes up.