Why won't my keyboard's \ key work when running W10?

I have two desktops using a single keyboard, monitor and mouse via a KVM device. One desktop is running Windows 7 but I've just upgraded the other from Windows 8 to Windows 10.

All was 100% well on both machines before the upgrade. The Windows 7 machine is still fine (as you'd expect!) but on the Windows 10 machine hitting the \ key on the keyboard has no effect whatsoever. On Windows 10 set up I chose "UK keyboard" as usual; I think I've always done whenever I've loaded any version of Windows.

So ... what has happened to my \ key?

(The sharper ones amongst you will have realised that I'm typing this on the Windows 7 machine!!!)

hTconeM9user said:

Hi did you make sure the BIOS and Drivers are up to date
Also you could download and install on your taskbar
An App called the character Map
I used it when I got stuck when I used 8.1

If there's a problem with the machine's BIOS then wouldn't I have had the same keyboard problem when I had Windows 8 installed? And as for the drivers, it's a fairly old bog standard Dell keyboard so I can't believe that its Windows 10 drivers will be be older than the Windows 8 ones.

I'll try to find the Character Map app though and download it tomorrow.

I installed the character map app which, yes, gives me a clunky solution to the problem.

Finding and installing a BIOS update for my ASUS motherboard has been a nightmare ... with no apparent end so I've given up.

Being unable to easily & 100% satisfactorily install a new operating system on a machine that's less than four years old is ludicrous. I'll reinstall Windows 8.1 which I wasn't very keen on but at least every key on the keyboard worked as required. I might even go back to Windows 7, which looked like a professional operating system rather than one designed for half-wits using computers as toys. In fact, I think I've still got XP SP3 somewhere ... what will I lose by using that? Not much