I previously had this problem. Every email I received was received in 5s. It took about 2 months or more before the problem was resolved. In about 3 weeks, I got the same problem again.

Previous thread: http://answers.microsoft.com/en-us/windowslive/forum/mail-sync/receive-multiple-copies-of-similar-emails/e532e822-3391-430b-ae31-801aa3741077

Could I please get a permanent solution to this problem? It's been frustrating waiting forever to get attention, then having the solution work only for a few weeks.