As title says... this trick is very easy and anyone can do it.
If you are logged in to computer with some other account here are the steps:
1. Go to Start button click on run (or just windows key + R)
2. Type CMD and press enter
3. A command window will open
4. Type net users
5. This will show you all the users of that computer.
6. Now type net user administrator * and press enter
7. This will ask you to enter a password
8. Enter the password you want to keep for the administrator
9. Re-enter your password to confirm it.
Thanks this is my first post here :)
You have changed the password of computer administrator. Now you can
logoff that user and can login as administrator with the password you