Choose exFAT or MS-DOS (FAT) for the format; Choose Master Boot Record for the Scheme; Click Erase; 5. When finished, the drive will be formatted and repartitioned successfully. Click the Done button. NOTE: exFAT is used on SDXC card (64GB and higher). NOTE: exFAT can be used on flash drives or memory cards to transfer files larger than 4GB. To format a drive on a Mac, you’ll need the built-in Disk Utility application. Press Command+Space to open the Spotlight search dialog, type “Disk Utility”, and press “Enter” to launch the app. You can also open a Finder window, select “Applications” in the sidebar, and head to Utilities Disk Utility.

• Format A Bootable Usb Drive
• Formatting A Flash Drive Mac
• Format Flash Drive For Bootable Mac Usb
• Format Flash Drive Mac Fat32
• Bootable Usb Disk Format Utility

WARNING: Formatting will erase all data on the device. Back up all your data before proceeding.

Windows FAT32 USB Drive in Mac Click on the “Erase” button on “Disk Utility” and choose the format as either APFS or Mac OS Extended. In most cases, your Mac will show the supported format by default and you don’t need to change it. On older Mac, you will see an additional scheme option, choose “GUID Partition Map”. Start the Lion DiscMaker app with your USB flash drive plugged in and with the Lion install file sitting inside your application folder. The app will give you the option of creating a bootable drive out of either a DVD or a USB keychain. Select the USB keychain option. Step 3 Wait for a while, and Recoverit will format your drive and start creating the bootable media. Step 4 Once it finishes, follow the next steps to restore data. How to Set the Computer Boot from the Bootable Media. Step 1 Connect your external drive to your unbootable Mac.

Instructions below are for 10.11.x (El Capitan) and 10.12.x (Sierra)

1. Double-click on Macintosh HD - or in the Finder menu clickFile > New Finder Window
2. Click the Applications folder - if using a Finder Window Applicationswill be in the left side menu.
3. Click the Utilities folder.
4. Double-click Disk Utility.
5. On the left side of the window are the drives connected to the computer. Select the capacity of the drive respective to the one containing the device you wish to format then click the Erase tab.
Example: If the drive is called 'NO NAME', directly above that, you should see the drive capacity of 'XXXX'. Select this capacity.
6. Verify Volume Format is set to MS-DOS file system or exFAT, Scheme is set to “Master Boot Record” (Do NOT select GUID Partition Map) then click Erase.

Instructions below are for 10.13.x (High Sierra)

1. Open Disk Utility. Please See Answer 20985: How to access Disk Utility macOS
2. In the top menu bar, go to View, and choose Show All Devices

3. Select the upper level of the drive you would like to format and click the Erase button

4. Choose how you would like to format the drive

• Enter a Name for your drive
• Choose exFAT or MS-DOS (FAT) for the format
• Choose Master Boot Record for the Scheme
• Click Erase

5. When finished, the drive will be formatted and repartitioned successfully. Click the Done button

NOTE: exFAT is used on SDXC card (64GB and higher).

NOTE: exFAT can be used on flash drives or memory cards to transfer files larger than 4GB.

NOTE: MacOS 10.6.2 or higher is required for exFAT file system. Some older operating systems must have a patch installed before they can use the exFAT file system.

NOTE: If the above steps do NOT resolve the problem or if the lock switch is missing or broken, please back up your data and request a replacement using our online web form.

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Each operating system could 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:

Format A Bootable Usb Drive

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: macOS Recovery Mode

Formatting A Flash Drive Mac

As an alternative, you can start your Mac in Recovery Mode. This will allow the system to automatically detect and repair directory issues. Recovery Mode will only allow required kernel extensions to load, preventing login items and startup items to load automatically. It can also help you isolate the issue depending on whether or not the issue goes away in Recovery Mode. If the issues you have during normal startup don't show up in Recovery 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 Recovery 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.

Format Flash Drive For Bootable Mac Usb

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.

Format Flash Drive Mac Fat32

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.

Bootable Usb Disk Format Utility

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