The other suggested fix for iTunes issues is to log out and back in with your Apple ID:
Freezes and frozen start-ups
Symptom: If your device doesn't start up or suffers from unexpected freezing in normal use, these three basic steps should help.
You can first try a "hard" restart: Hold the power button and the Home button at the same time until the Apple logo appears and the device restarts.
You can restore the device, as already described above.
Or if your device gets stuck on the Apple logo and won't restart at all, connect your device to iTunes and restart it there. While the device starts up, continue to press the Home button until a dialog box appears in iTunes that says: "iTunes has detected a (device) in recovery mode. You must restore this (device) before it can be used with iTunes."
You then select the device in the left hand column of iTunes, choose Summary, then Restore.
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