That will make it so his password doesn't expire but his post makes it sound like he's getting a login prompt when he boots whereas before, he wasn't but I'm not sure.
Are you required to press Ctrl+Alt+Del and enter your password before it will log you in or have you always required the user to enter their password and it all of a sudden is telling you that your password is going to expire?
Requiring the user to press Ctrl+Alt+Del in a non-domain environment is actually a registry entry. This is not enabled by default so if you didn't change the registry key to enable this option, I'd do some checking and see who was in your computer.
Here is how to disable that option: http://tweakxp.com/tweak1991.aspx
If this isn't what you are looking for and the post before mine isn't either, explain in detail what is happening and what you want to happen.