Apple MacBook Pro (17-inch, Late 2011) - Manual (Page 54)

54 Chapter 4 Problem, Meet Solution
If your MacBook Pro freezes during startup, or you see a flashing question mark,
or the screen is dark and the sleep indicator light is glowing steadily (not in sleep)
The flashing question mark usually means that the computer can’t find the system
software on the hard disk or any disks attached to the computer.
 Wait a few seconds. If the computer doesn’t soon start up, shut it down by pressing
and holding the power (®) button for about 8 to 10 seconds. Disconnect all external
peripherals and try restarting by pressing the power (®) button while holding down
the Option key. When your computer starts up, click the hard disk icon, and then
click the right arrow. After the computer starts up, open System Preferences and click
Startup Disk. Select a local Mac OS X System folder.
If the problem occurs frequently, you might need to reinstall your computer’s system
software. See “Repairing, Restoring, or Reinstalling Mac OS X Software” on page 56.
If your MacBook Pro doesn’t turn on or start up
Try the following suggestions in order until your computer turns on:
 Make sure the power adapter is plugged into the computer and into a functioning
power outlet. Be sure to use the 85W MagSafe Power Adapter that came with your
MacBook Pro. If the power adapter stops charging and you don’t see the indicator
light on the MagSafe connector turn on when you plug in the power cord, try
unplugging and replugging the power cord to reseat it, or try another power outlet.
 Check whether the battery needs to be recharged. Press the small button on the left
side of your computer. You should see one to eight lights indicating the battery’s
level of charge. If a single indicator light is on, connect your power adapter to
recharge. For more information about battery indicator lights, see page 56.