Try a hard reset as follows:
1) Remove the battery and unplug the DC power adapter.
2) Press and hold the power button for more than fifteen seconds.
3) Plug in the DC power adapter (leave the battery out for now)
4) Press the power button
Please post your positive or negative results here in your thread.
Help us by identifying your notebook completely.
HP has produced and brought to market more than a thousand different models of notebooks and desktop PCs over the years. It is difficult to help you if we don't know which specific model you own..
Remove the battery and look in the compartment where the battery was installed. You should see a Service tag with printed part number and a product name. Please post the p/n (with all alphanumeric characters) here. If you live outside of North America, it helps us if you post the country of purchase. Also post the installed CPU type. (AMD or Intel)
Don't forget to post the name of the installed operating system if you haven't already done that.
Best regards,
erico