Startup keyboard combinations have been around since the early days of the Mac operating system. Holding down specific keys while pushing the power button offer a plethora of options for troubleshooting when your Mac starts up.
Here are the most useful keyboard startup combinations:
|Key/Combo||What it does
|⌥ (Option)||Display all bootable volumes (Startup Manager)|
|⇧ (Shift)||Perform Safe Boot (start up in Safe Mode)|
|C||Start from a bootable disc (DVD, CD)|
|D||Start up in Apple Hardware Test (AHT), if the Install DVD 1 is in the computer|
|T||Start in FireWire target disk mode|
|N||Start from NetBoot server|
|X||Force Mac OS X startup (if non-Mac OS X startup volumes are present)|
|⌘-V||Start in Verbose Mode|
|⌘-S||Start in Single User Mode|
|Mouse button||Eject CD/DVD and start up from hard drive|
Most of these keyboard combinations will work with any modern Mac, but some models may have variations that work or don’t work.