Common causes:
- an add-on gone wild. Try Outlooks safe mode: http://www.outlook-tips.net/beginner/safemode.htm
- a damaged .pst file. Rename it and see what happens if Outlook creates a new empty one.
With a new empty pst-file and in safe mode, it likely will work correctly.
Kees
Why is my MS Outlook 2003 automatically closing by itself?
Paul

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