Eject (⏏) or F12 or mouse button or trackpad button: Eject removable media, such as an optical disc.

Disabled in macOS Mojave or later, or when using a firmware password.

Command-S: Start up in single-user mode.

To use the default boot image on the server, hold down Option-N instead.

N: Start up from a NetBoot server, if your Mac supports network startup volumes.

Or use Option-Dto start up this utility over the Internet.

D: Start up with the Apple Diagnostics utility.

If your Mac is using a firmware password, it ignores this key combination or starts up from macOS Recovery. Folders/Mails Disappearing on iMac/MacBook. Continue to press and hold the Shift key if you see the restarts. If there are pending repairs, this is when you will see the MacBook restaring before it continues. The booter will try and verify as well as repair the startup volume. If you lose important files, restore them either from the backup or via a Mac data recovery software. This is done by pressing and holding the Shift Key when you start up your MacBook.

Option-Command-P-R:Reset NVRAM or PRAM. Release all the keys to boot your MacBook Unexpected shutdown of your MacBook is one of the reasons for data loss.

If your Mac is using a firmware password, you're prompted to enter the password.

Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes.

macOS Recovery installs different versions of macOS, depending on the key combination you use while starting up. Or use Option-Command-R or Shift-Option-Command-R to start up from macOS Recovery over the Internet.

Command (⌘)-R: Start up from the built-in macOS Recovery system.Apple Diagnostics will run a series of hardware tests on the Mac, displaying a progress bar on.

Continue holding the D key until you see a screen asking you to select your language, then click on your language choice to proceed. Key Combination For Mac Startup Shortcut Turn on the Mac by pressing the Power button, then immediately press and hold the D key on the keyboard.

Keep holding until the described behaviour occurs. To use any of these key combinations, press and hold the keys immediately after pressing the power button to turn on your Mac, or after your Mac begins to restart.

Mac startup keys diagnostics