Without USB or reset disk, you can reset your windows 7 password with Windows built-in Administrator account.
Firstly, you start your computer and press “Ctrl+Alt+Delete” twice at the Login Screen.
Secondly, you just type Administrator in the username box and leave the password box blank.
Thirdly, you hit Enter key and then log into Windows system.
Finally, you go to “Start->Control Panel->User Accounts” to reset the forgotten password.