Usb Drive Bootable For Mac Os

Boot Mac from USB. Follow the below process to boot your Mac from bootable USB: Insert the bootable USB installer drive and go to “Apple Menu Restart”. When your Mac restarts, press and hold the Option key till “Startup Manager” opens. The Startup Manager scans and lists the drives that are connected and bootable. If you want to use your USB stick with an Apple Mac, you will need to restart or power-on the Mac with the USB stick inserted while the Option/alt (⌥) key is pressed. This will launch Apple’s ‘Startup Manager’ which shows bootable devices connected to the machine.

  1. Create A Bootable Drive Mac
  2. Bootable Usb Drive Creator Tool

Every operating system can crash at one time or another. While it's safe to say that macOS is more stable than Windows, it can still be affected by issues that prevent your computer from booting up. In such cases, you might need to boot your Mac from a USB flash drive to fix the problem. This article shows you two ways to boot Mac from external USB stick, as well as some troubleshooting tips in case Mac won't boot from the target USB.

Boot Mac from USB Option l: Startup Manager

If your Mac won't boot up normally, you can set it to boot from a different drive, such as a USB stick containing macOS installation files in bootable format. The drive will have to contain a version of the OS that is compatible with the Mac. As long as you have the bootable installation USB, you can start your Mac from the USB by accessing the Startup Manager. Here are the steps to be followed:

Create A Bootable Drive Mac

Step 1: Insert the bootable USB into Mac and power it on.

Step 2: As soon as the startup process begins, hold down the Option (alt) key and keep it depressed until you see the Startup Manager on your screen. If there is a firmware password on your Mac, hold down the Option key until you're asked to enter that password.

Step 3: You will now see the various startup disk options, and your USB will be listed there. If you click on the Up arrow right below the icon for the USB, the computer will only startup once using this disk. If you press and hold down the Control key while making your selection, it will be saved, and your computer will boot from the USB every time, as long as it is left in the computer.

At this point, you can also use the Mac installation disk to boot your Mac from. It will appear as EFI Boot, and it works on all computers running macOS 10.9 or higher.

Boot Mac from USB Option 2: Safe Mode/Recovery Mode

As an alternative, you can start your Mac in Safe Mode (Recovery Mode). This will allow the system to automatically detect and repair directory issues. Safe Mode will only allow required kernel extensions to load, preventing login items and startup items to load automatically. Hp printer drivers mac os. It can also help you isolate the issue depending on whether or not the issue goes away in Safe Mode. If the issues you have during normal startup don't show up in safe mode, they are most likely fixed. That means you can reboot normally and your system should be back to normal.

Step 1: Start your Mac and hold down the Shift key. You will see the Apple logo on your screen.

Step 2: When you see the login screen, you can release the Shift key and login to your Mac.

Step 3: To check whether your Mac has booted into Safe Mode, click on the Apple logo on the top left and then on About this Mac. In the window that opens, click on System Report… You should be able to see this:

How to Fix Mac Won't Boot from USB Drive

Sometimes Mac won't boot from USB as expected. If you are unable to select a different startup disk, it's possible that your disk is not showing up in Startup Manager. If you try Method 1 above but don't see your USB drive listed there, it could mean one of the following problems:

Compatibility: It is possible that the version of macOS or Mac OS X that you have on the USB drive is not compatible with the hardware. That means you won't be able to see it in the Startup Manager so, of course, you won't be able to boot from it. In such cases, you may need to burn a compatible macOS version on USB drive in order to be able to boot Mac from it.

Startup Security Utility: In certain cases where your Mac has the Apple T2 Security Chip (2018 and later devices), it may be your Startup Security Utility settings that are preventing you from booting from USB. In this situation, restart your Mac and hold down the Command + R keys when you see the Apple logo. This will put your Mac into Recovery mode. In macOS Utilities, go to Utilities >Startup Security Utility and sign in as admin. Under External Boot, select the second option - Allow Booting from External Media.

Option ROM Firmware: Another known issue is that Option ROM firmware will not load in Startup Manager until you press certain keys manually. To do this, use Method 1 to access Startup Manager. Once you are there, press Option-Shift-Command-Period. You should now be able to see the USB drive. This is not exactly a problem as much as a feature. If the USB contains Option ROM firmware, you will need to press those keys everytime to boot from your pen drive.

These two methods and the troubleshooting tips should allow you to boot from USB or in Safe Mode so you can then isolate the problem that's preventing your Mac from booting up normally.

These advanced steps are primarily for system administrators and others who are familiar with the command line. You don't need a bootable installer to upgrade macOS or reinstall macOS, but it can be useful when you want to install on multiple computers without downloading the installer each time.

Download macOS

Find the appropriate download link in the upgrade instructions for each macOS version:

macOS Catalina, macOS Mojave, ormacOS High Sierra
Installers for each of these macOS versions download directly to your Applications folder as an app named Install macOS Catalina, Install macOS Mojave, or Install macOS High Sierra. If the installer opens after downloading, quit it without continuing installation. Important: To get the correct installer, download from a Mac that is using macOS Sierra 10.12.5 or later, or El Capitan 10.11.6. Enterprise administrators, please download from Apple, not a locally hosted software-update server.

Bootable Usb Drive Creator Tool

OS X El Capitan
El Capitan downloads as a disk image. On a Mac that is compatible with El Capitan, open the disk image and run the installer within, named InstallMacOSX.pkg. It installs an app named Install OS X El Capitan into your Applications folder. You will create the bootable installer from this app, not from the disk image or .pkg installer.

Use the 'createinstallmedia' command in Terminal

  1. Connect the USB flash drive or other volume that you're using for the bootable installer. Make sure that it has at least 12GB of available storage and is formatted as Mac OS Extended.
  2. Open Terminal, which is in the Utilities folder of your Applications folder.
  3. Type or paste one of the following commands in Terminal. These assume that the installer is still in your Applications folder, and MyVolume is the name of the USB flash drive or other volume you're using. If it has a different name, replace MyVolume in these commands with the name of your volume.
    Catalina:*
    Mojave:*

    High Sierra:*
    El Capitan:
  4. Press Return after typing the command.
  5. When prompted, type your administrator password and press Return again. Terminal doesn't show any characters as you type your password.
  6. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the bootable installer is created.
  7. When Terminal says that it's done, the volume will have the same name as the installer you downloaded, such as Install macOS Catalina. You can now quit Terminal and eject the volume.

* If your Mac is using macOS Sierra or earlier, include the --applicationpath argument, similar to the way this argument is used in the command for El Capitan.

Bootable

Use the bootable installer

After creating the bootable installer, follow these steps to use it:

  1. Plug the bootable installer into a compatible Mac.
  2. Use Startup Manager or Startup Disk preferences to select the bootable installer as the startup disk, then start up from it. Your Mac will start up to macOS Recovery.
    Learn about selecting a startup disk, including what to do if your Mac doesn't start up from it.
  3. Choose your language, if prompted.
  4. A bootable installer doesn't download macOS from the Internet, but it does require the Internet to get information specific to your Mac model, such as firmware updates. If you need to connect to a Wi-Fi network, use the Wi-Fi menu in the menu bar.
  5. Select Install macOS (or Install OS X) from the Utilities window, then click Continue and follow the onscreen instructions.

Learn more

For more information about the createinstallmedia command and the arguments that you can use with it, make sure that the macOS installer is in your Applications folder, then enter this path in Terminal:

Catalina:

Mojave:

High Sierra:

El Capitan: