I have my pop account setup in Outlook 2007 and on my iphone. Not all of the mail that hits outlook also hits the iphone. It seems random. I'll get 3 messages in both places and then I'll miss 5 on my iphone and then I'll get 2 more on both Outlook and then Iphone. Apple has been no help except to tell me to reset the iphone. It's not worth having the phone if I'm not sure I'm getting all of my mail.