outlook 2003 send receive operation failed id 27
 

Outlook 2003 will not send/receive email.
Nothing happens. No error message.
Event viewer gives the following notice:
"outlook 2003 send receive operation failed id 27".
If I log out/in then Outlook will be back to full functioning send/receive
ability.
This will last for a while; then again Outlook 2003 will not send/receive
email.
Any idea?
Thks,
Enea