I'm trying to upgrade to the 4.2 update, but the iPhone will not back up "because the back-up was corrupt or not compatible with the iPhone." I've : *Updated to the latest iTunes *Gone into Edit > Preferences > Devices > Device Backup > Delete Backup (I deleted an iPod backup. The Device backups is now empty *Reset Sync History. *Uninstalled / Reinstalled *Delete back ups manually It still won't let me back up the phone, I have no idea what to do. Anyhelp would be greatly appreciated. I've got the latest iTunes and the iPhone is on Version 4.0.2.