This is what I tried already (none of these things worked):
- Started Outlook with the /safe switch
- Started Outlook with the /cleanprofile switch
- Reregistered OLE32.DLL
- Renamed outcmd.dat
- Uninstalled MS Office and reinstalled
- Applied SP3 to MS Office
- Created a new Outlook profile
The only thing that worked was logging in as a different user on the same machine, but there are so many custom setting on the correct user profile, that it would take a huge amount of time to recreate them.
The machine is an XP SP2 PC on a Windows domain with local profiles only.