The question is about the last step how to make sure that my iPhone has been unlocked.
Actually it's not that simple. The AT&T representative told me that I should simply perform a backup and restore of my iPhone to complete the unlocking. But how do I know it's unlocked?
I did a simple backup and restore while connecting to iTune. I didn't receive any message regarding unlocking when restore was completed. I read the discussion threads from Apple support forum.
First, connect iPhone with a computer via USB cable and backup your iPhone.
Second, select your iPhone and click on the Restore iPhone to original setting button (not to restore from your existing backup yet).
