If your Mac has a firmware password and you want to boot into Target Disk Mode you can’t just hold down T while the computer boots. It won’t prompt for a password or anything. To get around this I’ve been booting into systems, removing the firmware password, then booting into target disk mode.

Well there is a much simpler way to do this.

  1. Hold Option while computer is booting.
  2. Enter firmware password when prompted.
  3. When you see the local hard drive listed hit T.
  4. Congrats, you are now in target disk mode.

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