MacRumors.com

After the iPhone 2.2.1 firmware update, some users found they had persistent problems with iTunes crashing with both iPhones and even iPods. Apple has issued the following email to some of the affected customers:

Dear Customer,

Recently, we uncovered an issue which was causing iTunes to unexpectedly quit when synced with an iPod or an iPhone. This issue impacted a small number of users, and we have identified your account as potentially being affected.

If you have experienced this issue, please follow these steps in order to sync your iPod or iPhone with iTunes:
1. Launch iTunes
2. Select "Deauthorize Computer" from the Store menu
3. Enter your iTunes Store Account ID and Password, then click the Deauthorize button
4. Next, choose "Authorize Computer" from the Store menu
5. Enter your iTunes Store Account ID and Password, then click the Authorize button

Once you have successfully deauthorized and reauthorized your computer, you should be able to sync your iPod or iPhone to iTunes.

I sincerely apologize for any inconvenience that you may have experienced as a result of this issue.

Thank you for being an iTunes Store customer.
iTunes Store Team

The fix has been circulating on the internet for a number of days and many readers have reported that this procedure corrects the problem. Some, however, have to take the additional step of "purchasing" a Free iTunes App after following the steps before syncing will work again.