OE 6 Gone Crazy

After many hours of no activity, I sent a new E-mail to a new address,
but instead of sending my new E-mail to a new address,
it sent a duplication of an old E-mail to an old address
that was sent many hours before.

My new E-mail to my new address only went to my Outbox.

I restarted my computer, but the same thing happened.

How do I correct this "out of control" Outlook Express 6?
I am also running Windows XP and MS Office Pro 2003.

Your help will be greatly appreciated.
Thank You,
--
Ray10X10