I wanna try to help but the Vostro computers are Dell, not HP, are you sure you have the type correct?

BACKUP ANY FILES YOU WANT SAVED......THEN....

* As the computer starts, press on the keyboard until the Advanced Boot Options menu appears on the screen.

* Press the on the keyboard to select Repair Your Computer on the Advanced Boot Options menu, and then press .

* Specify the language settings that you want, and then click Next.

* Log in as a user who has administrative credentials, and then click OK.

* Click Dell Factory Image Restore.

* In the Dell Factory Image Restore window, click Next.

* Click to select the Yes, reformat hard drive and restore system software to factory condition check box.

* Click Next.
The computer is restored to the default factory configuration.

* When the restore operation is completed, click Finish to restart the computer.

The software is now installed as it was when the computer was first received.

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