Windows 11 keyboard input occasionally becomes corrupted, but a low-level keyboard hook appears to "reset" it

Question

Windows 11 keyboard input occasionally becomes corrupted, but a low-level keyboard hook appears to "reset" it

Tatiana Mathis 0

I'm trying to determine whether I've encountered a Windows 11 keyboard/input-stack issue rather than a hardware or keyboard-driver problem.

The symptom was intermittent: the S key would sometimes behave incorrectly in applications. In particular, an application could behave as though S were repeating when I held the key down, even though the behavior didn't appear to correspond to what the keyboard was actually generating.

I ran several tests to isolate the layer involved.

What I found:

The keyboard itself otherwise worked normally.
I wrote a small PowerShell test using a low-level keyboard hook to monitor keyboard events.
When the application was exhibiting the problem, the PowerShell monitor was still receiving the expected S key event.
Holding S down produced what appeared to be a single key event to the monitoring script, while the affected application behaved as though the key were repeating.
This made a physical keyboard/switch problem seem unlikely because the lower-level monitoring layer was seeing correct input while the application was not.
I then stopped and restarted the low-level keyboard hook.
Immediately afterward, the keyboard/application behavior was normal.
Importantly, stopping the monitoring script afterward did not cause the problem to return.
The keyboard has subsequently continued working normally for approximately an hour, including after terminating the monitoring script with Ctrl+C.

This produced an interesting sequence:

application input broken → register low-level hook → behavior normal → unregister hook → behavior remains normal

I'm wondering whether registering/unregistering a WH_KEYBOARD_LL hook can cause Windows to reset or reconfigure some portion of the keyboard input path, hook chain, or input state.

I'm not claiming that the hook is definitely "fixing" the underlying problem. It could be coincidence, or the state transition could be occurring somewhere else in the Windows input stack. I'm mainly interested in whether anyone has encountered a similar Windows 11 issue where:

The application receives incorrect/repeated keyboard behavior.
A lower-level keyboard monitor still sees the expected events.
Registering/unregistering a low-level keyboard hook causes the application behavior to return to normal.
The fix persists after the hook is removed.

I'm particularly interested in reports involving recent Windows 11 builds, keyboard hooks, Raw Input, WH_KEYBOARD_LL, HID/input processing, or applications receiving keyboard events differently from what a lower-level monitor observes.

Has anyone seen this behavior or know what Windows component/state might be getting reset when a low-level keyboard hook is registered or removed?

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Answer 1

Vikki-T 10,375 Microsoft External Staff Moderator

Hi Tatiana Mathis,

I can understand why this behavior is puzzling, especially since the low-level monitor reports the expected key events while the affected application behaves as though the key is repeating. The testing you have already done is very helpful in narrowing down where the issue may be occurring.

Based on the behavior described, this does not necessarily mean that registering or unregistering a WH_KEYBOARD_LL hook resets the Windows keyboard input stack. The improvement could also be related to a change in timing, application focus, message processing, or an internal key state being refreshed at around the same time.

Since the low-level hook receives the expected events, the issue may be occurring further along the input path, such as within the affected application, its message queue, its key-repeat handling, or another program that is intercepting or modifying keyboard input. Raw Input, low-level hooks, and standard keyboard messages also observe input at different stages, so their results may not always match exactly.

To narrow this down, could you confirm the following?

Does the issue occur in only one application, or in multiple applications such as Notepad?
What is the name and version of the affected application?
Which Windows 11 version and OS build are you using?
Are any keyboard remapping, macro, overlay, accessibility, gaming, or input-management applications running?
When the issue occurs, does changing focus to another application and then returning to the affected application restore normal behavior?
Have you been able to reproduce the same sequence more than once?

If the behavior occurs again, it may also help to test with a clean boot and temporarily disable non-Microsoft keyboard utilities or overlays. Comparing the behavior in Notepad with the affected application could help determine whether the problem is system-wide or isolated to that application.

At this stage, the observation suggests a possible application-level input state issue or interference from another input component, but there is not yet enough evidence to conclude that the low-level hook is resetting an underlying Windows component.

While my initial response may not fully resolve the issue, I truly appreciate your cooperation as we work together toward identifying the most effective solution. Thank you so much for your understanding.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

Vikki-T 10,375 Reputation points Microsoft External Staff Moderator

2026-09-04T13:02:32.3133333+00:00

Hi Tatiana Mathis,

It has been a while and I am writing to see how things are going with this issue.

Have you had a chance to check the replies provided?

Any update would be appreciated.
Tatiana Mathis 0 Reputation points

2026-09-15T05:51:21.5066667+00:00

I explained a bit more as an answer.
Tatiana Mathis 0 Reputation points

2026-09-15T05:52:23.33+00:00
Thank you. I did some additional testing and can clarify the behavior.The issue is not limited to one application. The freeze/repeating-input behavior occurs across applications. It is also not a particular letter repeating. When the keyboard enters the bad state, essentially any key I type, including letters, Space, and Delete, can appear to repeat after an input freeze.

The sequence I am consistently seeing is:

The computer resumes from sleep.

The keyboard backlight blinks during/around resume. The monitor has also occasionally blinked at the same time.

The keyboard may then enter a frozen/repeating-input state.

If I continue typing while it is in this state, the glitches tend to occur more frequently.

If I stop typing completely for approximately 15 minutes or longer, the problem can spontaneously stop.

Once it clears, the keyboard can remain normal for a long period.

I have reproduced this general sequence multiple times.

There was also a more specific S/C symptom that occurred when the keyboard was in a bad state. S and C would sometimes be dropped, duplicated, or otherwise behave abnormally, and this became more noticeable as the keyboard remained in the bad state. I disabled WinHotKey 0.70, an old keyboard hotkey utility that was configured to start automatically, and the S/C-specific behavior appears to have disappeared. However, the general freeze/repeating-input behavior remains, so I do not currently think WinHotKey explains the entire problem.

I also tested Logitech Options+ separately by stopping its updater service and terminating its running processes. The general problem still occurred, so Options+ does not currently appear to explain it either.

One particularly unusual observation was the WH_KEYBOARD_LL test. When I registered a low-level keyboard hook, the keyboard immediately began behaving normally and remained normal for approximately an hour. The keyboard backlight also stopped exhibiting the blinking behavior during that period. Ending the hook did not immediately cause the problem to return, although the problem eventually returned after subsequent testing. I agree that this does not establish that WH_KEYBOARD_LL actually resets the Windows keyboard input stack. It could be a timing, focus, message-processing, or internal-state effect. I am mainly mentioning it because changing the hook state has repeatedly correlated with a temporary change in the behavior.

Some additional isolation results:

The issue has occurred with two different physical keyboards on the same Windows installation.

Both keyboards work normally under Linux.

The keyboard also works normally in Windows Recovery/Command Prompt.

USB selective suspend has been disabled.

The relevant USB power-management setting allowing Windows to turn off the USB device has been disabled.

I have not found a Scancode Map or keyboard Upper/Lower Filter.

The keyboard is using the normal Microsoft HID keyboard drivers (kbdhid.sys/kbdclass.sys).

There are no obvious Logitech Options+ startup or scheduled-task entries.

WinHotKey is currently disabled.

The most interesting part to me is the relationship with sleep/resume and the delayed spontaneous recovery after a prolonged period with no keyboard input.

I would still be happy to test specifically in Notepad and compare it with other applications during the same active glitch. I can also provide my exact Windows version/build and the list of currently running keyboard/remapping/overlay software if that would help narrow down which layer of the input path is involved.

At this point, I am mainly trying to determine whether the behavior is occurring at the HID/input processing level, in Windows keyboard message processing, or because of another component intercepting input after sleep/
Vikki-T 10,375 Reputation points Microsoft External Staff Moderator

2026-09-15T10:57:05.21+00:00

Hi Tatiana Mathis,

Thank you for the thorough follow-up and for testing with two keyboards, Linux, Windows Recovery, and different startup utilities. These results make a physical keyboard fault less likely and suggest that the behavior may be related to an input or power-state transition within the active Windows session, particularly after sleep or resume.

The fact that the issue affects multiple applications, can clear after a delay, and temporarily changes when a WH_KEYBOARD_LL hook is registered is useful, but it still does not confirm which Windows component is responsible. The hook may be changing timing or input-state processing rather than directly resetting the underlying issue.

Since you can reproduce the sequence, please provide the exact Windows 11 edition, version, and OS build, along with the keyboard connection type and device model. It would also be helpful to test whether the issue occurs after a clean boot and whether disabling Fast Startup or updating the device BIOS, chipset, USB, and keyboard-related firmware changes the behavior.

If the issue can still be reproduced, I recommend documenting the sleep/resume sequence and submitting it through Feedback Hub under Devices and Drivers > Input and language > Keyboard, using Recreate my problem while reproducing the issue. This gives the Windows engineering team diagnostic information that cannot be collected through a user-to-user forum.

Please note that moderators and contributors in this forum cannot access Windows diagnostic systems or directly investigate the underlying input stack, but the detailed isolation results you have provided should make the feedback report much more useful.