Remote Domain user unable to login to computer

I have an odd issue. I have a domain user that moved out of state and took their computer with them. Before they left I made them administrator of their machine so that they could log onto the machine without being connected to the domain. Then once they are logged into the computer they can start their VPN session and connect to the domain and use their email, file services and ERP system. On Friday they changed their password but now they cannot sign into their computer. I have connected remotely to their machine as administrator and removed them from the machine as administrator connected to the VPN and re-added the user to the computer as administrator but when I log out and try to come back in to the computer as the user it still says the password is incorrect.

I tried to work around this problem and have the user sign in as a local account on that computer but when I try to add that user to the computer it will not allow it becuase the user has not been created but that is what I am trying to do.  

I have the user signed into her computer as domain admin then configured all their resources under the admin login but I need to have the previous solution work. What can I do to get that comptuer to allow the user to sign into that computer using their domain credentials so they can get to their home screen and start up their VPN and connect to their network resources?