The brightness settings disappeared and I don't know what else to do

Question

Hello everyone,

On February 29th, 2024, I updated my notebook (Samsung NP350XAA-XD2BR) to the latest version of Windows 11 (23H2). After the update, the brightness settings disappeared (again, for the third time). I cannot change the brightness using the keys (Fn+F2 and Fn+F3 in my case), nor through the display settings, nor through the notification bar. The screen brightness is stuck at 100%, which drains the battery quickly and strains my eyes.

What I've tried to solve the problem:

• I uninstalled and reinstalled the graphics card driver more than 3 times (I don't think this is the problem because everything was working perfectly before that. I even did this process with at least 3 Microsoft support agents).
• I restored the system to a previous date when the brightness was working (and it didn't work because one of my antivirus files got corrupted in the process and I had to reinstall my antivirus and my other browser). I couldn't do the process again because the system cleaned up the dates that I could restore.
• I ran the health check and restore health through CMD, and nothing happened.
• I contacted Microsoft support, and one of the agents created a registry entry in the registry editor (I think it was in a System and Policies folder in one of the HKEY_CURRENT_USER folders), and nothing happened either.
• All possible drivers on my notebook are updated (including through Samsung Update), and I only used drivers from official websites.
• I restarted my device about 10 times today just to see if it would come back.
• I also reinstalled the ISO (without deleting my personal files), and nothing happened.

Additional information:

• I use a digitizer display (which uses the HDMI port to work) for work, and after that, Windows stopped recognizing any HDMI device as well. It recognizes the commands made on it (since it has USB), but the image is not projected on it (I saw people with similar problems that the same thing happened). The display itself is working, and I even reset it to factory settings, and Windows still doesn't recognize it.
• This is probably the third time that this has happened after a Windows 11 update. The first time I had to downgrade to Windows 10. The penultimate time, the support agent was able to revert the system back, and today I did everything mentioned above a few times, accompanied by Microsoft support and sometimes on my own.
• I changed a setting (enabled "App Control in Browser and Device Security") in Windows Defender a little before the update. I don't know if this interferes, but that's it. Any help is greatly appreciated.

Answer 1

Especially for laptops, notebooks, and tablets.

First, check your sensor services, confirm those are running.

Search for Services app, Windows button + R and then types Services.msc, open Computer Management > expand Services and Applications > click Services.

Once in Services, scroll down to the three (3) sensor services, Sensor Data Service, Sensor Monitoring Service, and Sensor Service. Ensure these are all running and set to Automatic. Or, if they are running, stop the services and set them to Manual. Reboot and see if that helps.

Second, try https://support.microsoft.com/en-us/windows/change-screen-brightness-in-windows-3f67a2f2-5c65-ceca-778b-5858fc007041 The brightness may be set to the sensors for auto adjustment.

Third, if you know the maker and make of the graphics card, search for management software from that manufacturer. I have an AMD GPU and the AMD management software can handle brightness and so much more.

This links contains much everything you tried already, things I mentioned, and some other options. https://www.drivereasy.com/knowledge/brightness-slider-missing/

Last, boot into your BIOS and see if there display or brightness options in there. If you allow Windows to install updates for third-party software, there might have been a BIOS update you were not aware of. This could explain, partly, why a Restore Point did not help. While you are looking around in there, see if your motherboard has an newer firmware updates. So motherboards require each update to be installed in order to be fully up-to-date. Check the README and install instructions before hand.

Let me know if any of this works.

Justin