Unable to adjust screen brightness after upgrade WIN10 solution by registry

1, enter the registry we can search or press "Win+r" and then in the Open Run box we enter "regedit" Press OK to bring up the Registry Editor, as shown in the following figure.

2, OK in the registry we do not find, directly using the Registry Editor search function to search the "featuretestcontrol" option.

3, find the Featuretestcontrol option to change its numerical data to FFFF, and finally click OK, restart the computer can be effective.

Okay, here we go. Adjust the brightness of the screen to see if the problem has already been solved.