Dear elrosso,
I realize it has been some time since you posted your question, but I recently started experiencing the same symptom with Outlook 2003 on XP also. Was wondering if you discovered how to fix this problem?
Thanks for any help you can offer.
MikeT
When I open Outlook 2003 on XP it sends and receives emails as it should, then for now reason it stops recieving emails from all accounts. To rectify this issue I have to reboot Outlook and it works again for a while then does the same thing. Can anyone help or suggest why this is happening as it is very frustrating?

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