1 Copper

F11 and F12 (Brightness keys) not working

The brightness keys on my laptop are not working. When I click on the F12 key, it shows on the bar that it's increasing, but my screen's brightness is actually not increasing/decreasing. I've tried several methods, but nothing seems to work. I tried uninstalling and re-installing my device adapter that didn't solve it. Some suggested enabling/disabling the Fn key; I normally don't use the Fn key to increase brightness so I couldn't try that option. Every key/action that controls brightness does not work. Is there a solution or is this permanent? Thanks for your help. 

P.S. I use Dell Inspiron