I am finding this discussion very interesting, since I too have the same problem--although I am already using an IMAP account, since I use Mobileme for my mail. I do have a POP account and a Yahoo account as well, but they all seem to run fine through my Mobileme account. I do not get duplicate emails on my computers---just on my ipad (1). I have never been able to solve this problem. I will open an email, read it, delete it, and within a few minutes it will just download again.... What a nuisance!!!!