Simple answer - reset the cmos

Check in the manual for your the motherboard , or look up the procedure on the internet. Each brand will have a different location or procedure.

Unfortunately you may have to re - configure your computer when finished.

Try these options ...I've had success before with the first method .

http://www.askvg.com/how-to-reset-recover-forgotten-windows-nt-2000-xp-2003-administrator-password/

Contact manufacturers Support

If you're talking about the BIOS password, not the Windows password, it can be reset by pulling the computer's battery. Every computer has a small disc-shaped battery on the motherboard that supplies power to the computer when you turn it off or unplug it, in order to store things like the date, time, HD type, etc. If you take it out and put it back in, the BIOS password will be deleted. Of course, you have to take the computer apart to get at the battery, and once you pull the battery you will lose all BIOS information, but I've done it many times and it really isn't that hard. Newer computers will auto-detect the hardware, and you can reset the date and time.

hi :

its easy when the laptop compelet starting and showing this window contain user name and password now you press alt+del+ctrl then write in user name administartion ,password administrator then press ok ..

If all fails reinstall OS oh boy.