Holly -
I have the same issue!!! I have uninstalled... and re-
installed, I have repaired, and updated ad nauseum!!
I have compared the mso.dll files, too...
All to no avail!! What the F#^$%#$%????+
My client machines are all Windows XP Pro SP1 (haven't
gone to SP2, yet), and they also have MS Office System
2003 Premium installed (full compliment including
Outlook, Word, Excel, etc). On my wife's computer, I
share it, and have my own profile set up. She uses OE 6,
but I use Outlook 2003, and I have installed SpamBayes,
and MS Personal Folders Backup.