On Windows 10, Night light is a feature that reduces the blue light on the screen at night to help reduce eye strain and improve sleep quality. Similar to Apple’s Night Shift and Android’s Night mode.
However, if you enable Night light on your device, sometimes the feature may not work correctly — usually, after installing an feature update, such as version 1903, version 1809, or previous versions –. For example, Night light may not turn off automatically on schedule, even after restarting or powering off the device. In other computers, the blue light filter appears grayed out and there is no way to enable the feature.
In this guide, you’ll learn a few ways to try to fix the blue light filter feature on the new version of Windows 10. (If you can’t change the Night light settings because they appear grayed out, use this guide to reset the feature.)
How to fix Night light on Windows 10
On Windows 10, Night light depends on your computer’s graphics driver to adjust the color temperature to reduce the blue light. If the video card driver installed isn’t compatible with version that you’re running, there is a chance that the feature will be grayed out or it will not working correctly.
Update graphics driver
You should manually install the latest video driver to resolve this issue. You can do this by visiting your PC manufacturer’s support website to download the latest graphic driver — and use their instructions to update your device.
Alternatively, you can also try to reinstall the driver version already installed on your computer with these steps:
Search for Device Manager and click the top result to open the app.
Expand Display adapters branch and select the video card.
Right-click the device and click the Uninstall option.
Check the Delete the driver software from this device option (if applicable).
Click the Uninstall button.
- Restart your computer.
After rebooting your device, Windows 10 should automatically reinstall the latest graphics drivers available on Windows Update. However, it should be noted that if you checked the option to delete the driver from your device, you may need to reinstall the driver manually.
To ensure Windows 10 installs the driver back, go to Settings > Update & security > Windows Update, and click the Check for updates button.
Disable Night light completely
If you’re able to enable the feature, but it’s not turn off automatically on schedule, and updating the graphics driver didn’t fix the problem, the workaround is to manually disable Night light.
Use these steps to disable Night light on Windows 10:
Click on Devices.
Click on Display.
Turn off the Night light toggle switch.
Resetting Night light settings manually
Use these steps reset the Night light settings using the Registry to fix problem:
Type regedit and click the top result to open the Registry.
Browse the following path:
Inside the “DefaultAccount” (folder) key, right-click and delete the following two keys (folders):
Restart your computer.
Once you complete the steps, the Night light settings will be reset, and the feature should start working again.
Although Night light is a great feature coming to Windows 10, it’s not exactly new. F.lux is a third-party utility that has been around for years, and it works exactly the same as the Night light mode supposed to work.
If you want to give F.lux a try, at least until Microsoft fixes its own feature, you can learn how to get F.lux and set it up using this guide.
Reinstalling Windows 10
When nothing works, and you really want to use this feature, as the last resort, you can try reinstalling Windows 10 with the May 2019 Update using a clean install.
Update September 5, 2019: This guide was originally published in April 2017, and it’s been revised for the latest version of Windows 10.