Issues with 24H2 and UAC prompts and screen lock?

Question

-Edit: Adding what I have found to be the fix below my original post content

-Edit 2: It seems that my fix did not work for someone else reporting the same problem. My issues seemed to go away after updating my lock screen settings, but this does not seem to be a guaranteed fix.

Hello,

Shortly after updating to 24H2 on Windows 11 Pro, I've had extremely detrimental issues where the only fix I can find is to force a reboot of my device. I am on a domain joined Dell XPS 15 9500. Hoping someone might have an idea on what I might be able to try to fix these issues

1. After an hour or two from signing in, I will run into an issue where a UAC dialogue tries to pop up on my screen but never shows up. I am logged in as a standard user and have to elevate with my admin credentials. I tried waited minutes for it, and it never comes up on my screen. The only way I've been able to try and get out of this situation is by hitting Ctrl+Alt+Del. And when I do this, my input is all completely frozen. My screen will render with new items such as a new Teams message, but I can not click on anything and there is no input accepted from my keyboard. The only way I seem to be able to get out of this situation is to force a reboot.
2. After locking my computer and walking away for even a few minutes, I come back to a black screen. I'm able to see my mouse pointer, but that is it. No login screen, no background, nothing. Again the only way to fix this is to reboot my computer.

Things I've tried:

1. dism /online /cleanup-image /restorehealth
2. sfc /scannow
3. Installing all available windows updates and driver updates
4. I've looked through the event viewer but I have not found anything helpful so far

I have one other person on our domain who experienced the issue with the UAC prompt locking up Windows 11 Pro, which leads me to believe that this may not be a problem with my device. The laptops are of different makes as well.

Screenshot of my sysinfo:

***moved from Windows / Windows 11 / Performance and system failures***

My Answer: From what we can tell from testing, I believe the issue was somehow caused by windows spotlight being selected for the lock screen. I'm not quite sure why. But me and the other person experiencing this both had the issue go away after changing our lock screen to a static image. This looks to have resolved both the UAC freezing issue and the black-screen lock screen issue.

I'm not sure if he also used to have a static image before the update changed it windows spotlight, or if the windows spotlight is running into issues for other reasons. Everything seems normal now though so I'm going to leave my lock screen as a static image and monitor other users to see if they have similar problems

Answer 1

Hey Daisy,

From what we can tell from testing, I believe the issue was somehow caused by windows spotlight being selected for the lock screen. I'm not quite sure why. But me and the other person experiencing this both had the issue go away after changing our lock screen to a static image. This looks to have resolved both the UAC freezing issue and the black-screen lock screen issue.

I'm not sure if he also used to have a static image before the update changed it windows spotlight, or if the windows spotlight is running into issues for other reasons. Everything seems normal now though so I'm going to mark this as resolved.

Thanks!

Drew

Answer 2

Hello

Greetings!

Thank you for your update and sharing.

Have a nice day!

Best Regards,
Daisy Zhou

Answer 3

I have this exact same issue after upgrading to 24H2. Locking the screen and UAC prompts sometimes trigger a hang and forcibly shutting down or rebooting the device via remote management are the only ways to get out of the situation. HP EliteBook 645 G9, domain joined. Using the device as standard user and elevating with my admin creds as needed. Using MS Defender as antivirus.

Windows and MS Store apps are fully updated (build 26100.2033). Latest drivers and firmware are also installed. I've also tried latest chipset and GPU drivers downloaded directly from AMD instead of HP offerings to no avail. November updates are released tomorrow and I hope those fix this problem but who knows...

When the bug occurs, locking the screen ends up in a black screen immediately. Only mouse cursor is visible. The cursor may have a rubberband effect to it when you move it.

When UAC acts up, the prompt never appears. All I can see is dimmed desktop background. I can either wait until the prompt times out or press Ctrl+Alt+Del, but every single window, button, control etc is frozen afterwards. If there's a window which has auto-updating content visible, it seems to work just fine at background. If I had music playing, it keeps going just fine. But the whole GUI is completely non-responsive for all user input. Well, maybe not completely, if I click on taskbar it disappears and there's explorer.exe hang in event log.

Sometimes I can use the laptop for few days without any issues, today I had to reboot 3 times. I have managed to trigger the bug multiple times right after a reboot and logging in, then trying to run something elevated - BAM! UAC freezes and the everything is stuck again. It can happen anytime with any software.

It's not a Windows spotlight issue here, I'm using static image for both lock screen and desktop backgroud on all accounts. I tried disabling lock screen notifications, that didn't help. There's some Windows Hello -related error in event viewer (we are not using Win Hello), so I tried disable Win Hello using group policy. That didn't help either.

While troubleshooting this I've been logged on to my admin account for some time, launching tools etc elevated and the issues hasn't occurred even once. Maybe because on the admin acc the UAC prompt is just Y/N instead of asking for username and pw. Dunno, to me this feels like somekind of weird credentials issue.

Answer 4

EDIT: 12th November updates did not fix the issue.

Okay, some more testing. I tried disabling fingerprint reader and camera in BIOS because I had a feeling the issue has something to do with Win Hello. That didn't help. I've run sfc /scannow and dism restorehealth and the issue persists. It doesn't matter whether my laptop is at our office LAN / WLAN or at home, disconnected from our network infra.

At home I have 3 PCs which I have upgraded to 24H2. They all have a standard user as a "daily driver" and a separate admin acc for administrative tasks. No issues there at all, UAC and locking both work flawlessly.

Some generic crash information below:

Answer 5

Are you using an antivirus solution? If so, my issue seemed to coincide with unloading my antivirus for a couple of days. I'm not sure why that would fix a problem like this, but it's the only other thing I had directly tried that lined up with the problem going away