Strange booting issue

[AntiHeroUK]

I've been given a laptop to remove viruses from and after removing over 1000 different malware issues it wasn't running just as it should so I backed up any data and reinstalled using the restore partition on the hard drive.

After that you would think all was well but the laptop won't boot into windows itself from a cold boot or from manually restarting the machine. I have to press a key on the keyboard which then shows a _ blinking in the top left corner for a second or two then starting windows appears.

Now if the laptop has to restart due to updates or making startup changes by prompting me to restart, the laptop will boot into windows fine.

Just wondering if anyone can shed any light as to why this would occur.

I can't see any setting in the BIOS or Windows that would cause this.

Maybe I'm overlooking something simple?

Thanks for any help anyone can offer.

 

[AntiHeroUK]

After a lot of troubleshooting and testing basically every component, I decided to try booting without the keyboard installed and a usb keyboard plugged in instead. The issue vanished right away, and immediately reappeared when the standard keyboard was fitted back on the laptop.