Resetting admin password using AppleID
I've been trying to help out a friend who is trying to upgrade to Mountain Lion, but can't because they've forgotten their admin / user password.
I found this article about how to reset it by using your AppleID:
http://support.apple.com/kb/HT4798
However, he gets as far as System Prefs > Users & Groups > Change (to the right of the AppleID) and is prompted for a Password (I assume his AppleID password, but apparently its rejecting it.)
Not sure why (I'm already running ML perhaps), but when I click on Change I don't get prompted for a password, and am able to remove or add Apple IDs in there.
Any ideas how to sort this out much appreciated. (Assuming he's using the correct AppleID password!)
Thanks.