Outlook: How To UnStick Messages

If you use Windows Mail on Vista, you might find that sometimes messages get stuck in the Outbox and you can't send or delete them. Yet whenever you close the program, you get told that you have unsent messages. What's up with that?...

It's a known problem, but there is an update that should fix it. You can find a link to the update and what to do if that doesn't resolve the problem in the Microsoft KB article 941090:
http://support.microsoft.com/kb/941090