I found this playing while playing with my keyboard, when I had forgotten the Admin password of my desktop!And then trying an admin trick.
This easy hack can be used to login to password protected PCs, or any Pc of which you don’t have the pass. be it your own computer.This can save your precious files, lost if you reinstall OS onto your PC.
Make a good use of it.

1. On the Welcome Screen, where it asks to enter password, click on the user and when it asks for password…
2. Press Ctrl+Alt+Del and leave the keys and repeat it once more Ctrl+Alt+Del, then Backspace, followed by Enter.
3. Repeat step 2.
4. A screen pops-up asking you to enter the User and Pass., am I right?
5. I the user field, enter “administrator” and leave the pass. field blank.
6. Login and you’re done.Then you can go to Control Panel if you want to remove password from your user account or do what you wanted if its someone’s PC.

The HacK is that the Administrator account is never deleted and is the main Admin AC for Windows.