I've had a strange problem recently, my laptop has function keys which let me control the brightness of the screen,and these also double as my f1 through to f12 keys. I know I know there is a setting in the BIOS to let me choose if I want to have "normally an f1-12 key, hold down extra function key to access special functions" or "normally special function, hold down extra function key to access f1 through to f12".

The last time I successfully changed the brightness I was in linux mint reading a bright white pdf document late in the evening, and I lowered the brightness. When I did this I held the "fn" extra function key and used "f2" and "f3" while a little icon showed on the screen with a bar I could adjust left-right and the brightness varied. I shut down, took out the mint USB and thought nothing of it. I'm not sure whether I had ever adjusted the screen brightness before while in linux before that time.

A few days later I was in windows watching a DVD and wanted to brighten up the picture, but using the function keys didn't work, couldn't get the screen brightness to change.

I have been to the BIOS and switched from what I had before normally special function, hold down extra function key to access f1 through to f12" to the opposite option, and I'm in linux right now and it doesn't seem to be working whichever way I try to use the keys.
Please Help.
Thanks !
I didn't find the right solution from the internet.
References:
- https://www.bleepingcomputer.com/forums … rightness/
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