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If a Macintosh computer is having issues starting up, please try the following troubleshooting steps.

Wait

Occasionally after an update, the Macintosh will take longer than normal to start up. Wait at least 5 minutes for the start up process to complete.

Forced Shut Down

1. Press and hold the power button for 5 seconds. This will shut down the machine.
2. Wait 5 seconds.
3. Reboot

Reset the PRAM

1. Turn off the computer.
2. Locate the following keys on the keyboard: Option, Command (⌘), P, and R. You will need to hold these keys down simultaneously in the following steps.
3. Press and hold the Option-Command-P-R keys.
4. Turn on your Mac.
5. Continue holding the keys down until your Mac restarts, and you hear the startup sound for the second time.
6. Release the keys.

After resetting your computer’s PRAM, you may need to update your speaker volume, display resolution, and startup disk preferences. For more information about PRAM, see the Apple Support article about .

Reset the SMC (System Management Controller)

Macintosh Laptops with Batteries You Can't Remove

1. Turn off the computer.
2. Plug in the power adapter to a power source and the laptop.
3. On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
4. Release all the keys and the power button at the same time.
5. Press the power button to turn on the computer.

Note: The LED on the power adapter may change states or temporarily turn off when you reset the SMC.

Desktop Macintosh Computers

1. Turn off the computer.
2. Unplug the computer's power cord.
3. Wait fifteen seconds.
4. Attach the computer's power cord.
5. Wait five seconds, then press the power button to turn on the computer.

Macintosh Laptops with Removable Batteries

1. Shut down the computer.
2. Disconnect the power adapter from the computer.
3. Remove the battery.
4. Press and hold the power button for 5 seconds.
5. Release the power button.
6. Reconnect the battery and power adapter.
7. Press the power button to turn on the computer.

Adjust Wireless Network Settings

1. Turn off the computer.
2. Hold down the Option key at start up.
3. When you are offered the option to choose a network, select the X.
4. Finish the boot up process.

Boot to Recovery Mode and Run Disk Utility

Recovery Mode allows a number of options. Choose carefully.

1. Turn off the computer.
2. Hold down the Command and R key at start up. You can release the keys once the Apple logo appears.
3. Select a language.
4. On the Utilities menu, select Disk Utility.
5. Select Macintosh HD
6. Run a Verify
7. Repair any problems found.
8. Restart the computer.