Aug 17, 2020 N: Start up from a NetBoot server, if your Mac supports network startup volumes. To use the default boot image on the server, hold down Option-N instead. Disabled when using a firmware password. Command-S: Start up in single-user mode. Disabled in macOS Mojave or later, or when using a firmware password. T: Start up in target disk mode. The Utilities folder on the Mac OS X CD contains Startup Disk version 9.2, the control panel you use to select the startup disk for your computer. You need to use this version of Startup Disk to.
By default, your Mac starts up from its built-in hard disk, but a startup disk can be any storage device that contains an operating system compatible with your Mac. For example, if you install macOS on an internal or external drive, your Mac can recognize that drive as a startup disk. You can then follow the steps in this article to start up from it.
Use Startup Disk preferences
- Mar 24, 2020 Or use Startup Manager as your Mac starts up: Restart your Mac from the Start menu in Windows. Press and hold the Option (or Alt) ⌥ key as your Mac begins to restart. Select your Mac startup volume (Macintosh HD) in the Startup Manager window, then press Return or click the up arrow.
- Adding startup programs in Mac OS X is pretty easy and straightforward. To start off, click on the Apple icon appearing on the top-right corner and then select the option ' System Preferences.' Once the System Preferences window has been opened, find and double-click on the option ' Users and Groups.'
When you use Startup Disk preferences to select a startup disk, your Mac starts up from that disk until you choose a different one.
- Choose Apple menu > System Preferences, then click Startup Disk.
- Click the lock and enter your administrator password.
- Select your startup disk, then restart your Mac.
If you see a message that your security settings do not allow this Mac to use an external startup disk, check the External Boot setting in Startup Security Utility.
Use Startup Manager
When you use Startup Manager to select a startup disk, your Mac starts up from that disk once, then returns to using the disk selected in Startup Disk preferences.
- Press and hold the Option (Alt) key immediately after turning on or restarting your Mac.
- Release the Option key when you see the Startup Manager window.
If your Mac is protected by a firmware password, you can release the key when you're asked to enter the password. - Select your startup disk, then click the arrow under its icon, or press Return.
If you press and hold the Control key during this step, your selection is saved in Startup Disk preferences, so it persists until you change it.
If your Mac is using OS X Lion 10.7.3 or later, you can also use this method to start up from your Time Machine backup disk. Startup Manager identifies your Time Machine backup as ”EFI Boot.”
If you can't select your startup disk or start up from it
Check for these possibilities if you can't see your disk in Startup Disk preferences or Startup Manager, or your Mac won't start up from it.
Check for a compatible operating system on the startup disk
Make sure that your startup disk is using a version of macOS that is compatible with your Mac. If in doubt, use the same Mac to reinstall macOS on that disk.
To start up from an external disk with macOS Catalina 10.15 or later, the disk must connect via USB-A, USB-C, or Thunderbolt, not FireWire.
Startup Commands For Mac
Check startup security settings
If you're using a Mac that has the Apple T2 Security Chip, check the settings in Startup Security Utility. These settings determine whether your Mac can start up from another disk.
Check for Option ROM firmware
Bootcamp Startup Mac
If you're in Startup Manager and can't see a third-party startup disk, the startup disk could be using Option ROM firmware. To enhance system security, Mac computers with up-to-date software don’t show devices that use Option ROM firmware until you load their firmware. To do that, press Option-Shift-Command-Period while in Startup Manager. If your startup disk appears, do that each time you want to start up from it or from another disk connected to it.
If you're using a firmware password, the ability to load Option ROM firmware is disabled as an additional security protection.
Boot Camp Control Panel User Guide
You can set the default operating system to either macOS or Windows. The default operating system is the one you want to use when you turn on or restart your Mac.
Set the default operating system
In Windows on your Mac, click in the right side of the taskbar, click the Boot Camp icon , then choose Boot Camp Control Panel.
If a User Account Control dialog appears, click Yes.
Select the startup disk that has the default operating system you want to use.
If you want to start up using the default operating system now, click Restart. Otherwise, click OK.
You can’t change your startup volume to an external FireWire or USB drive while you’re using Windows.
To learn how to change the default operating system using macOS, see Get started with Boot Camp.
Restart in macOS
In Windows on your Mac, do one of the following:
Restart using Startup Manager: Restart your Mac, then immediately press and hold the Option key. When the Startup Manager window appears, release the Option key, select your macOS startup disk, then press Return.
If you’re using a portable Mac with an external keyboard, make sure you press and hold the Option key on the built-in keyboard.
Restart using Boot Camp Control Panel: Click in the right side of the taskbar, click the Boot Camp icon , then choose Restart in macOS.
This also sets the default operating system to macOS.
For more information about restarting in macOS, see the Apple Support article Switch between Windows and macOS.