There are far too many pests and I can even craft an email with javascript to create such a problem. Your issue is not concrete enough for me to tell if there is some pest involved, you have the preview pane enabled, the OS installed properly (Microsoft doesn't do this!) or just some other issue.
If this was me, I'd try running OUTLOOK /SAFE (start, run...) and see if it helps.
If this is a sporadic issue, then the issue can be today's users don't accept how unreliable the older OS and applications were. They show up and expect the OS and application to be fixed. Microsoft didn't fix it so I can't either. In Outlook 2000, a bug that was never resolved was what happens (often!) when I close Outlook when email is outgoing. Outlook no long runs until I endtask the old hidden program from the task manager.
Be aware you are looking at very old software.
Bob
When I respond to some (not all) messages or add an appointment, Outlook will shut down itself and gives the message : "Outlook has caused an error in <unknown>. Outlook will be shut down. If the problem keeps occurring, restart the computer".
I have reinstalled Outlook and reinstalled Windows ME, however the problems keeps occurring.........
What should I do ?

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