If you have a bootable CD/USB drive,some password tools can be burn to it and you can boot your computer from USB to run the software,so that you can recover/remove WIndows system password from USB.
Such as Windows Password Rescuer,here I just list the simple steps:
Step 1: Download Windows Password Rescuer
Step 2: Run it to burn to bootable CD/DVD or USB flash drive
Step 3: BIOS setting of your locked computer to boot form CD or USB
Step 4: Reset Windows password on a friendly window after Windows Password Rescuer starts.You also can use Windows Password Rescuer to add a new user with administrator privilege to your Windows when you can not find target user. With this New user account you can logon your locked computer directly to copy important data from the locked computer if you want to reinstall your Windows system at last.
http://www.daossoft.com/documents/how-to-reset-window-2000-xp-vista-win7-password.html[
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