Have an older HP DV9000 notebook running F11 x86_64.
Have been using the 'fn' key and the f7/f8 keys to both raise and lower the backlight on the book for quite some time now with no issues.
Earlier tonight, I added another user to my notebook and was even able to get onto their Gnome desktop and use the 'fn' key combos to lower the screen brightness, but now I can't get it to work again in EITHER my own user account OR the new one to RAISE the backlight again.
It's as if my keymapping suddenly just went poof...
I have never had to look for where this is was controlled or even know how it worked since it simply worked from the get go, but now that it is not working I need some pointers, please.