If i remember correctly unless you created a password recovery disk, the outlook might be grim, i had a similar problem a few years back, rather than spend countless hours searching for a solution, i just reformatted and reinstalled, i know that doesnt really help you, especially hearing bad news, maybe someone else on these forums has an idea,

There are several ways to get into a computer without a password.  First, try the old trick of powering it up and waiting until the login screen comes up.  Press Ctrl-Alt-Del twice and you'll see the old style login boxes.  Type Administrator in the top box.  Be sure the A is upper case and the rest is lower case.  Don't put anything into the password box.  Press ENTER or click OK.

If no Admin password was set, that should get you in.  Once in, go to the regular user's profile and set the password to whatever you want.

If that fails, try the stuff in your PM box.

For XP, if nothing else works, you should be able to find a legitimate commercial app that will help you 'break in to your own computer.' I saw it done once several years ago, but it required floppies and I can't remember the app's name. I do remember it was around $60.

Well the SAM file isnt that hard to bruteforce and dont take long unless you have a very long and advanced password.

I know i have done it on my own machine. Probably are some nice dos-boot disk or similar that can gethold of your sam and crack it really fast.

Good Luck

Well. I am in as Administrator. Thanks for getting me in. If i can not figure out the old password at least i can make a new user account.

Thanks MottiKhan

Does it request password info in safe mode?

I did not try it in safe mode. 

All i did was what MottiKhan said .  Put Administrator in user and left Password blank. That started the computer up as Admin. Then went to user account that i lost password and changed the password. Done, Every things good.  Way to easy.

http://www.grape-info.com/doc/win2000srv/security/ntpasswd.html 

Grab that.

It resets Admin passwords as well....cos if you've forgotten that one you're very likely up the proverbial without a paddle...

Good tool to have 'just in case'....particularly when the password is actually corrupted and thus impossible to know.  [it happens]

My password is imaginary.

But that means I can't type it in...

My password is ******

hey!

You stole mine, fuzzy!

I'm glad to see that you got it working, WeatherBound.   

Ouch!  Now my brain hurts.   

Mine password is ****** or It is ********.  Dang, I get a year older and My brain looks like ***********.

Password Hint - Me. And still could not figure it out. Ouch

Mine password is myname or It is password. Dang, I get a year older and My brain looks like that greysquigglythinginmyskull.

So how many of you use Pa55w0rd and think you are safe?