This might help:
http://www.pprune.org/newreply.php?d...te=1&p=5064940
Restore the PC to its original condition with the HP Recovery Manager if Windows Vista is not accessible
If the PC cannot launch into Windows, it may still be possible to use the HP Recovery Manager on the hard drive to restore the computer to its original operating condition by first pressing the Power button to start the PC, and then pressing the F11 key to start the HP Recovery Manager.
NOTE: Depending on the BIOS version, your computer may display multiple prompts during startup including F11 to start System Recovery. Pressing the F11 key on a computer with an HP factory image will start System Recovery even if the prompt is not displayed.
* If the HP Recovery Manager can access the hard drive, a prompt is displayed to backup the user files before beginning the recovery. Follow any on-screen instructions.