Solved Windows 11 24H2 Logitech keyboard's left SHIFT has started misbehaving

Hello.
It would be great to get some suggestions on what to look for, because googling hasn't given me any solutions that worked.

A year old computer with the combo of a Logitech keyboard K-270 and M185 mouse. Wireless (I suppose). The USB Bluetooth dongle that I plugged in the back of the computer doesn't seem to affect the input devices. Certainly no Unifying receiver in the system. The Logitech software doesn't find one.

To the problem:

Everything worked fine up to 2-3 weeks ago when I installed the latest Logitech drivers for my Logitech hardware, followed later by Logi Options+ and Setpoint drivers in various combinations while trying to resolve the problem that came up.
No success and the problem remained after I removed all the added Logitech software and reverted to the MS driver.

What happens is that the left SHIFT button doesn't behave the same as the right SHIFT one (which behaves properly).
The left SHIFT works for everything except the following letters:

(Note that this is a dual language keyboard (English/Greek) used mostly in English. Default is English (US QWERTY) with Greek as a secondary language with its own keyboard layout (Greek Polytonic) loaded
The things in parentheses are what the keys show on them.)

@ (numeric 2 + @)
E (same E for Greek + euro symbol)
C (another Greek letter (Ψ) + Copyright symbol)
N (same N for Greek)

What happens when I press left SHIFT and any of those 4 keys, is zilch. Nothing prints. Hard to switch to some capitals and combinations like SHIFT + c.
Whatever you see here with capitals E,C,N is done with the right SHIFT.

For both languages, all required packages are installed.
Sticky, Filter and Toggle keys are disabled.
Disabling Bluetooth (like I read on Google) made no difference.
Adding all the available Greek keyboard layouts and trying them, the same.

The On Screen Keyboard behaves as expected but then it uses a vanilla single English or Greek keyboard

If some utility I have installed messed up some setting by mistake, I can't tell yet. Nothing looks related to keyboards.

This is worse than The Elusive Pimpernel (from the homonymous movie).

Thanks in advance for any ideas to try.

I'm not familiar with these devices but I thought they worked through a 2.4 GHz radio channel (not bluetooth).
It seems the Logitech Unifying receiver can support up to six devices, the mouse can be connected through it ?

abactuon said:

I'm not familiar with these devices but I thought they worked through a 2.4 GHz radio channel (not bluetooth).
It seems the Logitech Unifying receiver can support up to six devices, the mouse can be connected through it ?

Click to expand...

The Unifying receiver links the mouse with the keyboard and as you said more devices than that.
But I don't have a Unifying receiver (they have a distinct color according to Logitech's info). Either it doesn't support the models I have, or the store took it out so they can sell it separately :)

If you put Ubuntu on a USB stick and boot into Ubuntu, you will know immediately if this is a hardware issue or a Windows problem.

I think you will find that all the keys work in Ubuntu.

Have you tried fresh batteries in the keyboard?

Your keyboard and mouse are wireless, but not wifi. Each one needs its own USB dongle connected. The keyboard is Unifying compatible, but the mouse has a Nano receiver which is not Unifying compatible.

You could also try plugging both receivers into front ports on your pc.

kanenas said:

Everything worked fine up to 2-3 weeks ago when I installed the latest Logitech drivers for my Logitech hardware, followed later by Logi Options+ and Setpoint drivers in various combinations while trying to resolve the problem that came up.

Click to expand...

Note that you do not need problematic Logi Options+ nor outdated Setpoint for them to work, unless you are changing something.

kanenas said:

Everything worked fine up to 2-3 weeks ago when I installed the latest Logitech drivers for my Logitech hardware

Click to expand...

I thought the drivers came with the Setpoint Software? Where did you get the drivers from? The last Setpoint ver was from 2023


I suppose you could try removing the driver from Device manager, rebooting to see if it finds a better driver?

kelper said:

Have you tried fresh batteries in the keyboard?

Click to expand...

And this ^

Try turning on 'Sticky keys' under Accessibility. This allows one finger typing - you press and release the SHIFT key and then type the letter.

Thanks guys,
I'll try to answer all questions...

Kelper, no Unix stuff. I haven't used it since the eighties and I don't have the stamina now I'm sorry to say.
I'll try new batteries. A few days ago one of Logitech programs told me that the batteries were good (around 70% full going by its bar).
Half an hour ago their Connection Utility told me it was low and 15 minutes ago Setpoint told me it was good again. Go figure. They are supposed to last a couple of years.
The USB dongle (I found it plugged in after all), is just a 2.4Ghz wireless. It works with both keyboard and mouse or you can connect them with their Connection Utility. Very picky dongle. It must be kept away from USB 3 devices and as close as possible to the keyboard/mouse. I'll get an extension USB 2 cable for it tomorrow.
Unifying software can't do much. The keyboard is not Unifying, only the mouse is. No point looking for a Unifying dongle. Setpoint or nothing, is probably sufficient.
Sticky keys? That would be the opposite to do in troubleshooting. Why would I prefer single finger typing when I can work as always using the right SHIFT key instead?

TairikuOkami, I tend to agree with you.

antspants, the original drivers were from Microsoft circa 2006 (this date is meaningless of course).
Setpoint 6.90.66 loaded drivers 6.0.45.0 circa 10/14/20 for both keyboard and mouse.

At the moment the problem remains with Setpoint and its drivers loaded up.
I'll see what happens after I manage to isolate the dongle from the USB 3 devices. Also I'll have to get some can of pressured air (or use my wife's blow-dryer with cold air and live to tell the story). Maybe some dust accumulated under the left SHIFT key or Caps Lock above it.
Watching the On-Screen keyboard, it seems the SHIFT key switches all the keys to lower case and then applies the wanted keystroke to get a capital letter. Why it happens only for a few letters, is anybody's guess. Or maybe not enough dust to do a proper job....

More in the near future.

Thanks a bunch.

kanenas said:

antspants, the original drivers were from Microsoft circa 2006 (this date is meaningless of course).
Setpoint 6.90.66 loaded drivers 6.0.45.0 circa 10/14/20 for both keyboard and mouse.

Click to expand...

OK. The last Setpoint listed for your keyboard was 2023-01-19
The last firmware update software tool was 2022-05-16

Was just curious if you’d tried it all.

Did you try Sticky Keys? Yes or no.

kelper said:

Did you try Sticky Keys? Yes or no.

Click to expand...

Yes, it works but what this means for the mentioned problem I don't know.
There has to be some sort of auto-sticking (everything becomes small case letter) when you press the SHIFT and this doesn't happen with the left SHIFT now.

antspants said:

OK. The last Setpoint listed for your keyboard was 2023-01-19
The last firmware update software tool was 2022-05-16

Was just curious if you’d tried it all.

Click to expand...

I tried the version I mentioned. The firmware update tool was 3.2.276959 and didn't support my devices.
I don't know their production dates. Even "modified" date shows 2025 for both.

Still investigating this problem but so far I've failed.

Steps taken since my previous post:

1) I took the keyboard to a shop and had them change the batteries and take out the left SHIFT and CAPS Lock keys and clean them up. They did but they were clean already. Got some other stuff while I was there...

2) The problem was still evident when I got home, So I used a USB extender cable, moved the Logitech wireless dongle right next to the keyboard and mouse and crossed my fingers.
Zero difference.

3) Uninstalled all Logitech software, rebooted and deleted all Logi folders. The driver for keyboard/mouse went back to Microsoft's 2006 version. The problem remained.

4) Back to install Setpoint. The drivers were updated to a Logitech one.
During its setup, it mentioned that it doesn't support all my devices and showed me a link for Logitech Options (without the + part). But that link was going to a dead page. The problem remained.

5) Uninstalled Setpoint and since all I had left was Options+ (1.90), I installed that.
Running the program, it showed a mouse, I clicked "Add Device' and it showed the Logitech USB Receiver for wireless keyboard and mouse (and a Bluetooth option that doesn't apply in my case).

6) I clicked the USB Receiver option, it asked me to turn off/on the devices (I hope it meant the keyboard and/or the mouse) but it could never find any device.
After a search failure, the previous screen would show USB Receiver for mouse. After going into search again and just backing up to the previous panel, the Receiver would show keyboard and mouse.

7) It seems the Options+ doesn't properly support my devices. Maybe the Options (without the +) will but I have to find that installer first.

8) New kid on the block. At about the testing time and even now, when I switch off the keyboard and then ON, the Windows Calculator pops up!!
I remember it being a choice in some utility (could be Logitech's though) which I never selected and now I can't remember where I saw it.

9) I can't imagine how some key combination affects now any driver installed.
At the moment, I use Sticky Keys as suggested earlier by kelper.
Later, I might throw those Logitech devices out the window...

Regards to all.

Remember, you need both USB dongles. One has the 'Unifying' logo and one hasn't.

The receiver for the mouse is often tored inside the mouse.

FWIW, I've been using the Microsoft Comfort Curve 2000 keyboards for years. I just really got used to this keyboard, and my fingers don't feel like adapting to anything new. It has good tactile feel and touch, and isn't super loud when you're typing on it.

However periodically, the keyboard will develop a key or two that stops responding. It's always been an issue of the Mylar film contact mating with the PCB under it. When I look, I've never seen anything, but I apply my fix and it seems to cure it. I take the keyboard apart, carefully clean the Mylar film and the mating PCB contacts and reassemble. Doing that I've been able to keep the keyboards I have working for many years. I've even worn most of the legends off one of them, but they keys still work great.

Last time I had the issue and had several of them with malfunctioning keys, I did a search and actually stumbled across a thread that had a more logical reason for the issue. I guess I fixed it by disassembling and cleaning it, but next time I may look into this information.

Fix Defective Keys in Comfort Curve Keyboard​

I would think this kind of thing might apply to any keyboard that has a similar construction with the Mylar film and PCB contacts under it.

kelper, I only have one dongle, unless the mouse has its own built-in.
I can't tell since I can only find its battery compartment.

I located and tried Logitech Options 10.24.3.0.
It had a hard time too connecting to the keyboard and the problem remained.

gunrunnerjohn just posted some interesting info that sort of matched what happens with my case. Except in my case, other than the mentioned 4 keys following the SHIFT, all the others work fine.

But the read up on the link he posted, got me to just stare at my keyboard trying to figure out how to take out all those keys for a proper cleanup or some good smacking :)

Looking at the keyboard, two things hit me. I knew about (1) but I ignored them since I don't use them.

1) There is a series of buttons over the standard keys. Sound control and such, turn off/on the PC and an almost submerged one with some button design on it.
I pressed it and the Calculator app popped up. That's what I had posted about on #14. I had seen it somewhere in the keyboard's description and tried it.
But in #14 it also came up on switching the keyboard on...

2) Why was only that calculator button submerged?

I pressed in different parts of it and pulled it, until it eventually popped up in the same height as the other keys.

And the problem disappeared !! :)
Left SHIFT behaves now the same as the right SHIFT.

It drove me up a wall but I never expected some sort of short on a key that I had pressed only once when I read its description.

But all's fine now...

I'll try Logi+ tomorrow to see how it behaves now and I'll add a post with the results to finalize this thread.

Thank you all for your great help.
Regards.

I didn't mention sticking keys as it didn't occur to me. Due to the way that the keyboard decoders work, a stuck key will usually affect a specific group of keys, so that makes sense.

I reinstalled Logi+ (v1.90), it installed the MS drivers (dated 2006) for my efforts, and all's still well :)

The troubleshooting can be successfully concluded.

Once more, I thank you all.
Cheers.