Clear all

Step by step (non-destructive) resets - SMC, NVRAM, Safe mode  



As an independent support guy for people & business with Apple gear I often get calls or emails requesting help on a Mac where the Apple provided reset steps solve the problem (in addition to those where TOTO, turn off turn on, does the trick). I have these steps (as cribbed from the Apple Support pages) recorded in TextExpander so I can quickly send them to people via email or message from any of my devices. I've pasted them below and you may like to take a copy for yourself and/or suggest amendments or corrections....

- - - - - - 

1a) SMC reset - laptop (2 minutes)

  • Shut down the computer.
  • Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
  • 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. (Do this a couple of times if you're unsure.)
  • Press the power button to turn on the computer.  

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

- - - - - - 

1b) SMC reset - desktop (2 minutes)

  • Shut down your Mac.
  • Unplug the power cord from the back of the Mac.
  • Wait 15 seconds.
  • Plug the power cord back in.
  • Wait five seconds, then press the power button to turn on your Mac.

- - - - - - 

2) NVRAM reset (2 minutes)

  • Shut down your Mac.
  • Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.
  • Turn on the computer.
  • Press and hold the Command-Option-P-R keys before the gray screen appears.
  • Hold the keys down until the computer restarts and you hear the startup sound, or see the big Apple icon, for the second time.
  • Release the keys.

- - - - - - 

3) Boot into Safe Mode (up to 15 minutes)

  • Shut down the computer.
  • Press the power button to start the Mac and immediately afterwards press and hold down the left Shift key until you see a progress bar or the Apple logo.
  • If your Mac has “FileVault” turned on you will be quickly presented with an initial “login” screen - which is actually just to unlock the hard drive. You will be asked to login again a bit later.
  • Your Mac will do some cleanup steps and show a progress bar. This may take up to half an hour - let it run even if the progress bar doesn't seem to move.
  • This should end up at the login screen with "Safe Mode" written in red at top right. If not, then Safe Mode didn't engage, shut down & try the procedure again.
  • Login to your account (you're still in "Safe Mode" so it may look a little different including a flickering screen, don't panic!) but don't start any apps or programs.
  • Leave the Mac like that for 5 minutes to "settle down".
  • Shutdown and restart normally. (This restart step is important - don't forget to do it!)

Note: This cleanup procedure deletes various "cache" files used by the operating system and apps. The next time they run they may have to recreate those cache files - so it is normal for the first restart of the Mac and the first launch of any app after a Safe Mode reset to take longer than normal.

- - - - - -