Your Trackpad, Mouse, or Keyboard Doesn’t Work
Your MacBook Air is a slick, sleek machine, but in the end it’s just that: a machine. This means that it’s just as dumb and helpless as any other collection of transistors and relays, so it can’t do all that much on its own. No, your MacBook Air needs you, and in particular it needs you to use a keyboard and trackpad (or an external mouse) to input commands, select options, and generally just give MacBook Air its marching orders.
Being the boss of your MacBook Air gets a lot harder when your tools of command — the keyboard and trackpad — don’t work. Fortunately the MacBook Air’s built-in keyboard and trackpad are rock-solid components that only rarely break down, but that doesn’t mean they don’t cause other types of problems.
You can’t press Tab to navigate a dialog
It’s usually easiest to navigate a dialog using the trackpad to select a check box or option, choose a list item, or enter a text box. However, some dialogs lend themselves to easier keyboard navigation, where you press Tab to move forward through the controls, or Shift+Tab to move backward. Or, I should say, dialogs that consist only of lists and text boxes lend themselves to easier keyboard navigation because, by default, OS X doesn’t Tab (or Shift+Tab) into other types of controls: check boxes, option buttons, pop-ups, sliders, tabs, and so on.
This is odd and frustrating behavior, but you can solve it with a simple keyboard command: press Control+F7 (remember to also ...