What version of Outlook do you have? What sort of mail account(s)? When
you get multiple copies of a message, are you getting *all* your mail
again, or just multiple copies of that new message?
I'm having the same problem. I get multiple copies of individual e-mails. It
is always e-mails from a commercial source or from one of the-mail lists I
subscribe to; never mail from an individual. I get two of some, I get three
of others, and I get 4 or 5 of others. Sometimes the number varies.