There are several methods to reset and recover your windows administrators password. The fastest method is to use a freeware tool like Offline NT Password & Registry Editor or the linux live distribution Austrumi.
The author of Offline NT Password & Registry Editor provide a bootdisk for his program while austrumi already is bootable. A detailed instruction for the first tool can be found at the authors website, with Astrumi you simply enter nt_boot when the command prompt appears.
You could also try to bruteforce your way in again but this is not recommended because the other two methods are easier and faster.
Last but not least this was taken from a user comment and not checked.
1) copy cmd.exe out of system32
2) rename as logon.scr
3) paste it back in system32 and replace current one
4) log off and wait for the screensaver. it will be a command prompt. use [net user]
[tags]windows, xp, 2000, password, reset, recover, administrator[/tags]

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No problem, it was my pleasure!
btw, the link that you published to my blog isn’t apparent, it’s only showing
as normal text, even if it’s clickable.
Cheers,
Kiltak
funny you should mention Austrumi…. i made a Detailed paper using this method… it can be downloaded from here
http://www.codelinx.net/smashing_windows.pdf
just to give an idea how to use this distro for account access