Control key acts as if it is stuck periodically

I have had this issue now with two computers and I cannot find anything that is causing it.

I disabled sticky keys.
I replaced the keyboard
I replaced the operating system
I replaced the entire computer

Yet, the problem keeps coming back. If I press the Ctrl a few times it will go away. However, if I press S it will act like I pressed Ctrl+S though usually it is the scroll wheel that is when I get most annoyed as in a web browser, rather than scrolling, it will zoom in and out.

I am in an active directory domain which is the only common denominator between this computer and the previous, though the previous one also had Window key getting "stuck" as well so if I pressed D, the desktop will show as everything will minimise.

Anything you can think of that can assist me in going in the right direction is greatly appreciated. Since it now a brand new computer with brand new keyboard where I just copied over my profile.

I have yet to try this with a different login to see if it is profile specific, but since it is so sporadic it is hard to tell.

Jonathan Weinraub

Posted 2015-08-12T16:06:43.633

Reputation: 375

Perhaps you have some accessibility setting enabled that makes the Ctrl key act as a toggle instead of a key that you have to hold? edit: oops, that's sticky keys I'm thinking of – Hayden Schiff – 2015-08-12T18:48:49.320

But what is weird it is intermittent. I will be sitting here reading a website for example, not touching the keyboard once, and I scroll down using the scroll wheel and it starts zooming. If I press control key a few times, it will stop happening, or eventually it will just go away on its own. The fact I replaced the computer and the keyboard makes it much more confusing to diagnose. I really need to try a different profile to see if it happens there as well as it is the only thing that can be considered the same. – Jonathan Weinraub – 2015-08-12T19:34:53.100

Do you have anything that could be interfering with your keyboard? If it's a wired keyboard, you could be getting crosstalk from a nearby wireless device or even another cable (especially a poorly secured one). If it's wireless keyboard, it could mean something else broadcasting on the same frequencies or something. (this is a bit of a shot in the dark, but intermittent issues tend to be caused by hardware rather than software) This would especially make sense if your replacement keyboard is the same exact model as the original keyboard.

– Hayden Schiff – 2015-08-12T19:41:33.807

I hate wireless devices, so it is a wired microsoft ergonomic 4000 keyboard. I replaced it with an identical model. I use a wired logitech mouse. I never suspected interference. Plausible. – Jonathan Weinraub – 2015-08-12T20:04:33.600

I also resolved this issue by disconnecting/reconnecting my Dell USB KB522 keybaord. – Kelbizzle – 2018-01-24T17:33:59.393

I had same problem. It ended up being caused by low batteries in my wireless logitech keyboard. – Johnny – 2018-09-22T20:44:33.140

– Tomas – 2019-12-06T13:27:07.013

I have this problem too; and I have Autohotkey installed (with one line script) and I'm using TeamViewer... not sure if any of those programs could cause it. – Tomas – 2019-12-06T13:27:42.457

Answers

Generic fix for this generic issue: press stuck key or `Ctrl`+`Alt`+`Del`, `Esc`.

Symptoms: This issue is not limited to Ctrl, but can occur with any other modifier key (Shift, Alt, Win).

Recovery: Most of the time, Ctrl+Alt+Del re-sets key status to normal if this is happening. (Then press Esc to exit system screen.)
Another method: You can also press stuck key: so if you clearly see that it is Ctrl which got stuck, press and release both left and right Ctrl. This allows system to see key press and release events (again) and thus detect correct status of these keys.

Cause: This occurs when the operating system did not notice releasing a key. But what can make the operating system not noticing a key release? I guess the answer to this can be very tricky and almost undiscoverable, because it might easily originate in subsystem seemingly non-related to keyboard. For example, badly written driver for some hardware creates a delay during which Windows skips the detection of released key. This is difficult to answer and could be very difficult to debug.

Scope: I have also seen this on many various computers, regadless of model or make. From my observation, this was not common up to Windows 7, but became more common in Windows 8 and 10. If the above recovery works, do not suspect your hardware, it is typically a software issue.

Note: If you have connected multiple keyboards, Ctrl+Alt+Del has to be pressed on the keyboard which has the key stuck. Pressing it on the other keyboard does not reset state of the stuck key.

miroxlav

Posted 2015-08-12T16:06:43.633

Reputation: 9 376

"But what can make the operating system not noticing a key release?": Wireless Keyboard with a low battery? Thank you for your Ctrl+Alt+Del, that worked magic. I have been having this issue with my wireless keyboard lately. – K.Dᴀᴠɪs – 2018-01-13T09:27:18.230

@K.Davis – wireless devices are a good catch. I forgot to mention them because I'm using wired keyboard. But the above problem is present with wired keyboards, too. – miroxlav – 2018-12-07T14:47:36.347

I found the solution because I got this issue with different laptop and for each one the fix is different. I have found the cause because of software conflict that is some software trying to use your keyboard at the same time making the ctrl key stuck.

For temporary fix you can try each of the following to see which one will work for your laptop:

Press both ctrl at the same time
Press both ctrl + alt at the same time (Dell 1545 worked)
Press both ctrl + shift + alt at the same time
Press both ctrl + shift + alt at the same time including the Fn key (Lenovo)

If it still does not work, opening the on-screen keyboard from control panel can temporarily unlock the ctrl key

However for a permanent fix, I downloaded SharpKeys and disable the Right Control, this has solved the problem. So you should find which of the two ctrl keys is causing the problem and disable one of them using this software. It should work. Else you may have to disable both and use on screen keyboard if you need the control key.

Guvin

Posted 2015-08-12T16:06:43.633

Reputation: 101

This always work for me, nice one @Guvin! – Giulio Caccin – 2016-06-20T10:20:34.540

This works for me, but I cannot understand why... – Hoàng Long – 2017-01-06T08:45:14.933

Just pressing the Fn key helped get me out of the issue. It's an odd thing to get stuck in and frustrating to get out of. I tried the other things like pressing right click and left click, all that. None of that worked except for the Fn key.

Works on Dell Inspiron 15 3000 Windows 8.1.

Hope this helps!

Faun C.

Posted 2015-08-12T16:06:43.633

Reputation: 31

-1

I moved my wireless router and vonage transmitter for wireless phones 4 feet away and reconnected my keyboard after re-installing batteries in keyboard. Problem solved for Logitech wireless keyboard.

Jim

Posted 2015-08-12T16:06:43.633

Reputation: 1