When I try to wake my computer I move the mouse or press the keyboard to wake it but nothing happens. I went to system preferences and the place to ad this but it is shaded where it want let me click this option. This is what it tells me but want let me add. "If you use a bluetooth keyboard or mouse, and your computer goes to sleep, you can press a key or click your mouse to wake your computer". How can I make this option available to allow it to wake my computer.