Brightness-Keyboard Illumination-Mission Control keys not working

Hey there,

It souns like you have some keys that are not working as expected on your built in keyboard. I recommend these steps from the article named:

One or more keys on the keyboard do not respond

http://support.apple.com/kb/ts1381

1. If the function keys on the top row of the keyboard are not working as expected, see Mac OS X: How to change the behavior of function keys.
2. If the issue persists, use Keyboard Viewer to help isolate the issue:
   1. Click the Language & Text pane (Mac OS X v10.6) or International pane (Mac OS X v10.5.8 or earlier) in System Preferences.
   2. Click the Input Sources tab (or Input Menu tab in Mac OS X 10.5.8 or earlier).
   3. Click the Keyboard & Character Viewer "On" checkbox to select it (click the Keyboard Viewer "On" checkbox in Mac OS X 10.5.8 or earlier).
   4. From the Input (flag) menu, choose Show Keyboard Viewer.
      

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All the best,

Sterling

My macbook pro has exactly the same problem as yours. Sometimes it works, sometimes it doesn't. I've checked the keyboard setting but without luck. Help!

I had the same problem and was able to solve by going into the keyboard preferences and unchecking "adjust keyboard brightness in low light".

Hope it helps!