Please HELP, months trying to resolve this issue.

Situation:
User's password is about to expire on the NT domain, on an XP PRO workstation.
User is part of the XP PRO local power user's group, NT domain users group.
User attempts to change the password for the NT domain on the XP PRO workstation.
User receives message: You do not have permission to change your password, message from the XP PRO workstation.
User must then go to an NT workstation, change password, then logon to domain on the XP PRO workstation.

I cannot find out how to resolve this issue, have been trying for months please help!!!!!!!