Fn key for adjusting the brightness is not working (Dell Vostro)

Closed
Sammmi - Dec 8, 2016 at 03:21 AM
Hello,

Don't know why the function key for adjusting the brightness is not working. When I press Fn+F4/F5, the little bar appear but the brightness can't be adjusted. All other function keys are okay, I hv tried changing the battery plan and enable/disable the auto-adjusting, but it's still not working.