Message sticks in Outbox - Outlook 2002

[Jim]

My messages stick in the Outbox or until I click something
else, like the Sent Items Folder, Deleted Items folder,
Calendar, Send / Receive, etc. The "Send Message
Immediately" option is enabled. I am running the Exchange
Server service. I rebooted the Exchange Server to see if
that helps but it does not. Any ideas will be greatly
appreciated.

Thanks
Jim