PRAM RESET

Option keyplusCommand keyplusP keyplusR key


Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. You can release the keys after about 20 seconds, during which your Mac might appear to restart.

  • On Mac computers that play a startup "chime", you can release the keys after you hear the startup "chime" two times.
  • On Mac computers newer than 2016, you can release the keys after the Apple logo appears and disappears two times. 



SMC RESET 


  • Shut down your Mac.
  • On your built-in keyboard, press and hold all of these keys:
    • Shift  on the left side of your keyboard
    • Control  on the left side of your keyboard
    • Option (Alt)  on the left side of your keyboard
  • While holding all three keys, press and hold the power button as well.
    Notebook keyboard with all 4 keys pressed
  • Keep holding all four keys for 10 seconds.
  • Release all keys, then press the power button to turn on your Mac.