If you’ve forgotten your Windows password and you don’t have an install CD laying around, there’s no need to worry. Not only are there half a dozen complicated ways to reset the password, you can do it easily with the Offline Windows Password editor.
Of course, if you do have a Windows CD, you can reset your password the easy way with a simple trick.
Note: this should work on all versions of Windows, but if you are running Windows 8 or 8.1 and also using a Microsoft Account to login to your computer, you’ll need to reset your Microsoft Account password using a web browser on their web site.
Read more about: How to Reset Your Windows Password Without an Install CD