I have an old first gen iPhone that I want to use now as an iPod Touch. It still has the sim card but it wont sync. The error message says, "iTunes could not back up the iPhone because the backup session failed." The phone still has the sim card. I was able to upgrade the software to iOS 3.1.3.
I already tried powering down the phone and restarting it. I used iTunes to do a restore to the original settings. Any other suggestions?