Since Microsoft has been sparing no effort to increase the market share of Windows 10, the Windows 10 brightness not working gets more and more popular. You should resolve the Windows 10 brightness not working error, otherwise it might cause possible problems while watching movies or other content, which makes it harder to lessen eye strain on Windows 10. The issue also emerges when you upgrade to a new Windows 10 build. The problem mainly occurs when users started to upgrade their Windows operating system from Windows 8 to Windows 10. What Is Windows 10 Brightness Not Working Problem? In this article, we will show you the steps required to fix Windows 10 brightness not working issue. When the error occurs, you cannot adjust the screen brightness up or down, which could be annoying under certain circumstances. There are reports that Windows 10 brightness not working for a few users. How to Fix Windows 10 Brightness Not Working Problem