For resetting administrator password apply following steps:-

     A. Boot using Windows XP Setup CD and follow the instruction like Accepting EULA, etc.


    B. When it asks to repair your existing Windows-installation, accept it and press "R" to run the repair.

    C. Setup will start repairing your Windows and will start copying files, etc.

    D. After a few minutes setup will restart your system and when it restarts don't press any key when it shows "Press any key to continue..." otherwise Setup will start from the beginning. Don't press any key and setup will resume where it left.

    E. Now it'll start doing other tasks and will show a small progress bar with a few details in left side.

    F. Look carefully at the details and when it shows "Installing devices", press +F10 keys in your keyboard.

    G. It'll open a Command Prompt window. Now type nusrmgr.cpl and press .

    H. It'll open the same "User Accounts" window which you see in Control Panel.


    I.  Now you can remove or reset any account password without any problem.