Outlook - Outlook Express 6 Outbox not empty

This just started two days ago.  Emails with no attachments will send and g=
o into the sent box.  Emails with attachments are left in the out folder an=
d it comes back and says Warnings when it sends them.  It does send them bu=
t it does not move them to the sent folder and if I do not manually move the=
m it will send them over and over.  I have Norton security.

Any ideas on what to do?

You're using Outlook Express? This is an Outlook newsgroup. Outlook
and Outlook Express are two very different programs. If you have an
Outlook Express question, please ask it in an Outlook Express
newsgroup or forum, since that is where the Outlook Express experts
hang out.

Ken Blake, Microsoft MVP