My son is trying to purchase some additions to a game but when accessing the App Store he is asked for the restriction pass code. However we don't recall setting one up for him and he hasn't been asked for this before. Why? How do we find out what it is? This is since upgrading to version 5.1.
iPod touch, iOS 5.1
what you can do is backup and restore
If you restricted in-app-purchases in Settings/General/Restrictions, and you don't remember the restriction code anymore to disable the restrictions, you'll have to set up the iPod as new device again, without using the latest backup, the restriction code is part of the backup and can't be changed by restoring the device from a backup that has been taken after the code has been set.
How to back up your data and set up as a new device
If there are no restrictions set, the code he is asking for is the iTunes ID password, to be able to purchase and download. If you have forgotten that one, follow this article to reset it:
How do I find out what the restrictions pass code is
