How to start a Mac in safe mode

Mac question: Something just went wrong, and I need to start my Mac (or iMac) in safe mode, or something like safe mode? Can this be done on a Mac?

Answer: Yes, Mac computers support a "safe mode" boot process. Here are the steps needed to start your Mac/iMac in safe mode:

  1. Make sure the computer is powered down.
  2. Press the power button to start it.
  3. Immediately after you hear the startup sound, press and hold the [Shift] key. (Don't do it until you hear that sound.)
  4. Release the [Shift] key when you see the Apple icon and progress indicator.

A Safe Boot takes longer than a normal boot, so be patient during the boot-up process. If everything went well, you will see a "Safe Boot" message on the login window.