We don't go around just giving out critical security information. It is quite possible to recover and even reset any users password on any microsoft system. XP/Server (editions)/vista.. yes even vista.
The experts here, know that a lot of questions pertaining to the recovery of or resetting of an administrators password on any system but especially on a server is normally someone that is not supposed to have the administrators password.
I know and many other experts on this site know how to do it. But it potentially crosses the line of legal and illegal boundaries.
Now if by a chance you are the network administrator for the company that you are working for, or educational facility, you can call the computer manufacturer of your system and explain to them your problem. They will be happy to help you as would I if you were able to prove to me a legit situation.