Keyboard locked out after Windows 10 upgrade.

Product Name: HP Spectre x360 - 13-4158ca
Operating System: Microsoft Windows 10 (64-bit)

1. I recently had to reinstall windows 10 on my laptop because of a failed ssd. I've managed to reinstall windows 10 using a bootable USB media.

2. Install process and user setup using the keyboard was normal and un-eventful

3. Device manager initially showed several question marks on some of the devices, but after re-installing the drivers from HP support website, all of these disappear.

4. However on restart, the keyboard and the touchpad are disabled. I cannot make any entries via the keyboard or touchpad at all. I can only use the onscreen keyboard and mouse.

5. Uninstalling the SYNAPTICS touchpad driver fixes the touchpad, but the problem with keyboard still remains.

6. Device manager now shows 2 keyboards HID Compliant Keyboard and Standard PS/2 keyboard. I don't have any external keyboard or docking station connected.

7. I know the physical keyboard works because the UEFI Hardware diagnostics shows functional keyboard AND I am able to make use of the keyboard while I enter the PC user data during the OS setup. UEFI Systems Extensive Test also does not report any failures.

THE Question: Is there any setting that I need to change to get the keyboard to work or do I have to delete anything? I have tried to delete either or both of the keyboards reported by device manager but this doesn't seem to work.

Any suggestions would be wellcome.

Thanks.