オリジナル投稿者： George Gibson ,
Methord-1; Reset the System Management Controller to Fix- 1. Shut down Mac and connect it to your MagSafe adapter and a wall outlet as usual. 2. Hold down the Shift+Control+Option+Power button for a few seconds at the same time. 3. Release, then boot the Mac as usual Method-2: Try a Keypress Sequence to Fix- 1. Press the Power / OFF button once – this will bring up the dialog box which you can’t see 2. Press the “S” button – this is the shortcut to sleep the Mac 3. Hold down the Power button until a hard shut down is forced 4. Wait about 15 seconds, then hit the Power button again to turn it back on. Hope this might help you.