I am having this same problem, and it's REALLY annoying!

I'm using Outlook 2003 on a Dell Dimension 1100 Windows XP desktop computer that is only 2 months old. This computer was purchased to upgrade (a bit) the 3-to-5-year old Dell Dimension 2350 Windows XP desktop computer I had been using. Office/Outlook 2003 was also on that older computer, but Outlook on that computer never used to exit unexpectedly. (By the way, I've never used Outlook Express here at work, so my problem isn't migration-related.)

My new Dell computer is running a free 90-day trial of McAfee Security Center (only because it was bundled; when the trial ends, we'll probably uninstall it and use something else).

The only other thing I can think of to tell whoever is willing to troubleshoot this issue (thank you!) is that I tried troubleshooting this myself by doing something that I think I saw advised in another forum, and that was to uninstall everything listed in the ADD-IN Manager and the COM Manager. (I don't know how to re-install any that I SHOULD have.)

Thanks!