Power on Password on HP Probook 455

[dooby1953]

Hi,
 
My problem is I cannot now use my Probook 455 notebook as when I boot I get directed to BIOS Power on Password and my password does not work although I have never changed it.
 
I was having a problem with notebook occasionly shutting down so I have been trying to run the UEFI system tests but I could not run the full set as the only tests available were short tests on HDD and Memory.
I contacted HP and they kept on sending me different UEFI program downloads but none worked any better.
I then noticed that in the BIOS a lot of options were " Greyed out " and unavailable to change.
The next thing I did was to be fatal as I was able to log into the BIOS as an Administrator which is when I noticed there were other users in the BIOS Administration box. I then decided to remove them and just left myself as sole Administrator and I did not change the password.
I followed the instructions and rebooted for the changes to take effect and ever since then I have been uinable to get past the Power On Password screens, eventually getting the " HP Authentication Failed Message " and please switch Off to try again and re-enter password.
There is no " Key or Numbers " in a dialogue box so most of the solutions I have found will not work.
 
I know there are many previous posts regarding this subject but these all seem to be 2-3 years old and not relevant to my notebook and the only thing HP could offer was to change the Mainboard for £200.
 
Please help if anyone knows how to overcome this problem I will be eternally grateful.
 
Best regards,
                                Mike