This question already has an answer here:

Brightness not working Acer Aspire One 756-2623 with Ubuntu 12.04. Also the mousepad right-click isn't working ether. I'm completely new to Ubuntu and Linux in general.

How do I fix it?

merged by Luis Alvarado May 4 '13 at 12:18

This question was merged with How to control Brightness because it is an exact duplicate of that question.