12 Startup Key Combinations of Every Mac Technician
Know your Mac startup key combinations. Every Mac technician knows them and uses them on a daily basis.
Startup key combinations are so important, and if you are unfamiliar with them, you’ll want to bookmark this page as a good reference post. In fact, we’ve gone the extra mile for this post and created a downloadable infographic for the Mac Masters’ community.
Safe Mode verifies the startup disk, repairs directory issues, disables unnecessary kernel extensions, prevents startup login items, disables user installed fonts, and deletes cache files (in font, kernel, and system).
Keys: Hold the Shift key when starting up
Shows available startup disks to choose for booting.
Keys: Hold the option key when starting up
The Mac will startup to an available OS on a CD, DVD, or USB. You can perform the same basic function when using the “Startup Manager”.
Keys: Hold the C key on startup
Starts up into internal diagnostics (Apple hardware Test or Apple Diagnostics). Holding Option+D will boot to the same test but over an internet connection rather than the internal hard drive.
Keys: Hold the D key on startup
This key combination resets the PRAM or NVRAM of the Mac (the type of reset depends on the type of machine). For more information, review support.apple.com/HT204063
Keys: Hold the command+option+R+P keys when starting up
This starts up into the internal recovery system (partition on the drive). Holding command+option+R or shift+option+command+R will perform the same result but will establish the recovery system over an internet connection rather than using the partition of the hard drive.
Keys: Hold the command+R keys when starting up
Starts up the Mac to an available NetBoot server. Holding Option+N will boot to the default NetBoot boot image.
Keys: Hold the N key when starting up
Target Disk Mode
Target Disk Mode (TDM) allows files to be shared between 2 Macs. One Mac in TDM is connected to a second Mac not in TDM using a FireWire, Thunderbolt, or USB-C cable. The Mac not in TDM now can access files from the Mac in TDM like when using an external hard drive.
Keys: Hold the T key when starting up
This will start up the Mac into the macOS startup volume. This is useful when the Mac has been starting up into another volume (like a Windows partition). Using the Startup Manager can also achieve this same function.
Keys: Hold the X key when starting up
By holding any of these keys/buttons, it will force the Mac to eject any removable media (such as CDs or DVDs).
Keys: Hold Eject, F12, mouse button, or trackpad when starting up
Starts up the Mac into “Single User” mode. This allows the technician to have access tot he Unix system before fully starting up into the macOS.
Keys: Hold the command+S keys when starting up
Verbose mode provides additional details to what the Mac is doing during the startup. This is especially helpful when attempting to figure out why a Mac is freezing on startup.
Keys: Hold the command+V keys when starting up.
If you haven’t already, sign up today and join the email list where you’ll receive a promo code to download this digital goodie FREE and 20% off infographic prints.
This graphic would be perfect as functional art at your repair workbench, office, or home. Head over to macmasters.net/shop and order one of our many options to be mailed directly to you.
Join the Mac Masters community, you’ll receive all the newest Mac Masters updates as well as some exclusive goodies only available to the Mac Masters community. One of which is our Mac Troubleshooting Basic. This is the essential troubleshooting framework that separates the Mac Masters from the average Joe.