How to hack Windows XP Admin Passwords

HACK No 1:
H A C K N o 1:
------------------------------------------------------------------------------
at logon screen press: Alt+Ctrl+Del you will be prompted for username and password

enter user name => administrator enter password =>
(do not enter any password)
and Voila!! you get into system as Administrator.....

This has worked because at setup time most users have not entered the administrator password
ps: after login chage admin password from control panel so next time you have control of that machine
REVERSE:
**********
If some has done this to your computer than you can always change administrator passwords
even if you dont know it
....
=> what you have to do is

1. go to command prompt
2. type control userpasswords2
3. a new screen will appear like this=>
4. click on administrator and give new password and it WILL NOT ASK YOU FOR OLD PASSWORD
   

-----------------------------------------------------------------------------