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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===
#Press and hold the power button for 5 seconds.  This will shut down the machine.  
#Wait 5 seconds.
#Reboot
===Reset the '''PRAM'''===
#Turn off the computer.
#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.
#Press and hold the '''Option-Command-P-R''' keys.
#Turn on your Mac.
#Continue holding the keys down until your Mac restarts, and you hear the startup sound for the second time.
#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 [http://support.apple.com/en-us/HT204063 NVRAM and PRAM].

===Reset the '''SMC''' (System Management Controller)===
====Macintosh Laptops with Batteries You Can't Remove====
#Turn off the computer.
#Plug in the power adapter to a power source and the laptop.
#On the built-in keyboard, press the (left side) '''Shift-Control-Option''' keys and the '''power button''' at the same time.
#Release all the keys and the power button at the same time.
#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====
#Turn off the computer.
#Unplug the computer's power cord.
#Wait fifteen seconds.
#Attach the computer's power cord.
#Wait five seconds, then press the power button to turn on the computer.

====Macintosh Laptops with Removable Batteries====
#Shut down the computer.
#Disconnect the power adapter from the computer.
#Remove the battery.
#Press and hold the power button for 5 seconds.
#Release the power button.
#Reconnect the battery and power adapter.
#Press the power button to turn on the computer.
===Adjust Wireless Network Settings===
#Turn off the computer.
#Disconnect Ethernet cable if connected.
#Hold down the '''Option''' key at start up.
#When you are offered the option to choose a network, select the '''X'''.
#Finish the boot up process.

===Boot to Recovery Mode and Run '''Disk Utility'''===
Recovery Mode allows a number of options.  '''Choose carefully'''.
#Turn off the computer.
#Hold down the '''Command and R''' key at start up.  You can release the keys once the Apple logo appears.
#Select a language.
#On the Utilities menu, select '''Disk Utility'''.
#Select Macintosh HD
#Run a Verify
#Repair any problems found.
#Restart the computer.

===Reinstall Last Combo Update===
Installing the last combo update from Apple may help with startup and general performance issues.  Use this option if the Macintosh boots up.  
#From the Apple Menu, select '''About this Mac'''.  Note the version of OS you are running.  
#From the [http://www.apple.com/support/osx/software-updates/ Apple Updates site], download the combo update that matches your version of OS.
#Install the update.

===Turn Off '''File Vault'''===
#From the Apple Menu, select '''System Preferences'''.
#Open the Security and Privacy preference.
#On the File Vault tab - turn off File Vault.

[[Category:Macintosh]]