I've set up a new domain user account for one of our client's employees. I randomly generated a password for the user account and set it up so the user has to change the password on first log in. We use the default Windows Server 2008 R2 password policy.
Now I'm on the phone with said user, tell the user the temporary password, explain the password rules and they're unable to change the password. The new password is simply rejected.
I explain the password rules again and the user assures me that the password complies with those rules. So I try to log in to the account myself, use my own custom password as the new password and it works right away.
This suggests to me that the user is incorrectly assuming that the password complies with the password policy but is unable to see the mistake.
Without asking the user for their password, how can I determine what the problem with their password is?