If Outlook has any add-ins installed, try disabling them. That includes an Avast email scanner add-in if there is one.
Outlook > Tools > Options > Other tab > Advanced Options button
But if the problem is the Avast email scanner you will need to take extra care with incoming and outgoing emails, as they will not be scanned.
Mark
I am using Office 2000, which is no longer supported by Microsoft. I keep getting the rather annoying message " Outlook has encountered a problem and has to close". I can restart the program immediately and it runs again for 15 minutes or so - the times are irregular. I have used the 'Repair' facility under Help but it has not made any difference. If I send an Error Report, I only get the offer of a free trial of Office 2007. I am using XP Professional with an Avast virus scanner. Any help would be appreciated.

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