Why not update my yahoo email on my iPhone?

Why not update my yahoo email on my iPhone? Suddenly my email yahoo will not download emails on my new iPhone. A few days passed without me an e-mail, then I logged on to my web box letter and noticed that my iPhone does not receive e-mails of news. I removed the yahoo my iPhone and added back. I deleted all my email account on my iPhone and only added yahoo mail. I restored my iPhone OS and now yet upgraded to version 4.0.1. Nothing seems to work. OH! I even put my yahoo email account in someone else's iPhone and all e-mails updated at the same date as they would on my iPhone and arrested and the same place. Very frustrating! Please help!

One of the more interesting available in the iPhone software update 2.0 is the ability to get new emails, contacts and calendar of events sent your device automatically. The catch: If you do not want to pay $ 100 for MobileMe and you do not have a Microsoft Exchange Server lying around, you are stuck pulling data or manually syncing to your computer. But if you're willing to roll up your sleeves, you can set up push e-mail and wireless contact and calendar syncing using the free Microsoft Exchange service Mail2Web. What's the Big Deal with Push? If you have never worn BlackBerry business problem, you may be wondering what makes push so special. Let's start by e-mail: No push e-mail address, your phone checks with your server every now and then to determine whether or not you have new messages it take to get the mail from your email server. With push e-mail, your phone receives an alert whenever a new mail arrives he pushed from the server to your phone as it becomes available.

iPhone iOS 4.0 IN-HAND, RELEASED and Previewed! – AppJudgment