Hi,
Try this: Power off the laptop, then when you power it on, keep tapping the ESC key. When a blue menu comes up, press F11 to run system recovery. When recovery comes up, choose trouble shoot this PC, advanced, HP System Recovery. Follow the prompts. If all goes well, this will restore the laptop to an 'out of box' state (i.e like new when you bought it)
Let me know what happens