We use a single Exchange server and some of the users have IPhones they connect to their email with. Over the weekend the power was out at the office. Yesterday the power came back on and I powered on the server. Everything is working except the users IPhones no longer download messages as they come in they have to hit fetch (sen/receive) where before they did not have to. I have other users with Droids and Blackberries and they are still working. And the Iphones can send/receive if you do it manually but not automatically. I don't see how the mail server being down for a few days would make this happen.