Using Office 2007 and Windows XP

This just started last week. When I "reply" to an email I have received,
(not "reply all) I end up getting a copy of the email sent to myself. But
this only happens in subfolders of my inbox, not the inbox itself. For
example: I receive an email in my inbox -- I "reply" -- email gets sent to
the original sender.

If an incoming email is directed to a subfolder because of a rule, when I
"reply" there is a copy of that reply email delivered to the same subfolder
as the original email.

Hope I'm explaining it clearly. Any ideas?