Yes wrote:
GlowingBlueMist wrote:

On 3/28/2018 11:23 PM, Yes wrote:
I have a MS ergonomic keyboard (PS/2) I've been using for quite a
few years now. Until a few days ago, it worked as expected.
However, now the OS (Win 8.1 Pro 64-bit) does not recognize it. I
have not changed my hardware nor have I added/removed any software.
My USB mouse works.

When I enter BIOS during the boot up procedures, the keyboard
works. I can move around BIOS. I searched my BIOS settings
looking for legacy devices and did not find anything.

Once my OS starts, the keyboard is not seen. For example, I've
tried typing, function keys, using Ctrl+, and so on. Nothing
happens.

What I've done so far:
1. use Device Manager to remove and then re-install the driver
2. unplugged the keyboard, turned off the pc, booted up, shut down,
plug the keyboard back in and boot up
3. scavenge a PS/2 keyboard from another computer to see if that
would work. It did not.

Is the problem hardware related? If so, the mobo or the keyboard?

I've thought about buying a PS/2 to USB adapter to use for the
keyboard, but I don't know if that would work. I'd like to keep
using the existing keyboard (the ergonomic design does make a
difference to me) if the problem is with the PS/2 connector on the
mobo. But if the pc recognizes the keyboard (when I'm in BIOS), it
doesn't seem like it's the mobo PS/2 connector.

FWIW, I've connected a wireless keyboard from my other pc till I get
this problem fixed.

Thanks,

John

Visit a local thrift shop and purchase an old PS/2 keyboard to test
with. In my neighborhood used keyboards can be had from 2.99 on up
at the two thrift shops that I visit, Habitat for Humanity and
Goodwill. If it works properly then it is time to look into your
problem keyboard. It could be something as simple as a bent pin on
the plug to broken connection where the wire goes into the plug to
actual wiring problems in the keyboard.

Since you are working with a USB wireless keyboard for now if the
replacement keyboard works from a thrift shop I would personally try
to swap keyboard cables. A little soldering or if you are extremely
lucky a matching plug at the keyboard end and you might be back in
business. If swapping the keyboard cable does not fix things it
sounds like time to visit Ebay and see if you can find the same
keyboard on the cheap or else purchase something modern in the same
format.

I already tried another PS/2 keyboard and had the same results as with
the MS keyboard.

I'll probably end up buying a new USB wired keyboard to replace my
existing PS/2 k/b. Just want to cover the bases before going that
route.

Reading the reviews of some PS/2 to USB adapters at newegg was rather
interesting. I discovered that not all adapters will work with any k/b
- something about the circuitry and OS.

Thanks,

John

Check out your Filter keys or Sticky keys settings.

https://answers.microsoft.com/en-us/...4-498ab5f05496

In some cases, you might have to turn it on, then turn it off
again, in the settings, to get it to "take".

It's possible an update turned it on.

*******

You could try booting an alternate OS, or try
entering the BIOS with the keyboard, to check
that it's not actually the keyboard that's blown.

Paul