If your Mac suddenly refuses to boot up properly, you might need a bootable macOS USB installer to make repairs. But how do you create such a disk if all you're left with is a Windows 10 computer? Fortunately, there's a great tool that you can use for free to create bootable macOS media on a USB drive in a Windows 10 environment. This article shows you how to download a macOS DMG file, format a USB drive using a GUID Partition Table, burn the DMG to the drive and boot your Mac from the USB. All the steps except the last one are done on a Windows 10 machine.

Part 1: Download macOS or Mac OS X DMG File

Sep 27, 2021 Boot Windows on your Mac from external hard drive. After creating a bootable external hard drive, follow the steps below to set it as boot device. Connect the external hard drive to the Mac computer. Click the Apple icon and open “System Preferences”. In the “System Preferences”, click “Startup Disk”. Jun 25, 2020 Create bootable USB drive with Mac Disk Utility. Now that you have the installation files ready on your Mac, you can move them to your USB drive for future use. To install macOS on an external hard drive: 1. Connect the USB to your MacBook. Open Disk Utility by following Applications → Utilities → Disk Utility.

The first step is to get the DMG disk image file for the version of macOS that you want. You can get a copy of the latest macOS version from Apple download portal or App Store here. There are also several other direct download sites that offer various versions of Mac OS X in DMG format rather than the standard APP format that runs on Mac. Since you're working in a Windows environment, you need the DMG rather than the APP file.

macOS DMG Download Link:

Part 2: Easily Create a Bootable macOS USB from Windows 10/8/7 PC

You have now formatted the partition of USB drive. It's time to download UUByte DMG Editor for Windows. Although this is a premium software, you can use the initial free trial period to create a bootable macOS USB on Windows 10. After installing the application, follow the sequence of steps shown below:

Updates (Dec 8, 2020): The latest version of UUByte DMG Editor is able to format the USB automatically.

Step 1: Right-click the software icon on desktop and select 'Run as Administrator' from the contextual menu. Choose 'Run' when prompted.

Step 2: Insert your formatted USB drive, and click 'Burn' tab on the main screen.

Step 3: Click 'Browse' button to import macOS dmg file into the program. And select the USB drive name from the second row. You can also set a volume labe for that USB drive.

Step 4: Click 'Burn' button at the bottom to start the process. You will see a progress bar and wait around 10 minutes to get it done.

Step 5: Once the progress bar is at 100%, a bootable macOS USB is ready. After that, you can use that USB drive for installing macOS.

This is one of the easiest way to create a bootable macOS USB on a Windows PC. The steps are simple and instructions are pretty clear.

Part 3: Format USB Drive to GPT If Failed

If the USB drive created in above step was not seen as a bootable device on your Mac, then you need to take an addtional step before burning. That's formatting the USB to GPT.

Mostly, the USB drive was formmated to FAT32 in default when being shipped out from the factory. However, FAT32 can be only used for installing OS with legacy BISO, which doesn't work for macOS. So the next step is to format your USB drive in the GPT partition style in order to burn installation files to the desired USB drive. You can do this in Command Prompt as admin. In elevated Command Prompt (Ctrl+Shift+Enter), input the following series of commands followed by Enter after each line:
List disk
Select Disk X (X stands for the USB drive name that appears after the previous command)
Convert GPT
Create partition primary

Part 4: Boot Mac from macOS USB Drive for Installation

Now remove the USB drive and insert it into the Mac computer. To boot from the disk, you need to hold down the option key when you hear the boot chime. This will take you to the Startup Disk Manager, where you should be able to see the USB drive. It might have a different name, but as long as it is bootable, you'll be able to see it there. Once you select it, the computer will boot from the disk and the macOS installation will begin.


Flashing Error: You might receive a flashing error message at the end of burning process. Please don'y worry and ignore this error. The USB becomes a bootable disk and you can use it to install macOS even this error pops up.

About Official EI Capitan DMG: There has a serious bug in the official release of OS X El Capitan, which contains .pkg installer only. The burning process will fail for sure. Please use this modified EI Capitan DMG file instead, which was approved a good option.

Registration Failed: Please make sure the computer is connected to Internet and no proxy or VPB is running during registration. If the problem still exists, please send an email to support team asking for a new code.


The whole process might look a bit complicated if this is your first time, but just follow the instructions in this article and you should be fine. That being said, you need to be careful when downloading the DMG file and formatting your USB drive. If you don't do these two steps correctly, the output drive from the UUByte DMG Editor software won't be bootable, which means you can't install macOS from that USB drive, and you may need to do the whole thing over again.

Make External Hard Drive Bootable with EaseUS Todo Backup (Easiest Way)
Create a Bootable External Hard Drive via CMD
Install Windows 10/8 on External Hard Drive (Edition Limited)

'Hi, what's the best way to make an external hard drive bootable? You see. Like copying all the Windows boot files to it so that I can boot Windows 10 from the bootable drive. Please, an easier way is much more appreciated.'

There are many significant reasons for creating a bootable HDD or USB drive that carries a user's customized Windows operating system. For example, when your PC unexpectedly shuts down and can be never turned on due to hard disk failure or system corruption, you can still easily start the computer from the bootable drive. A bootable external hard drive also does great help when a computer's dead or crashed. Besides, with a bootable external USB drive, you can use your own operating system wherever you go and whenever you like. To enjoy these advantages though creating a bootable external hard drive, you have three workable methods to choose from.

Method 1. How to Make an External Hard Drive Bootable with EaseUS Todo Backup

Applies to:Windows 10/8.1/8/7/Vista/XP (32-bit and 64-bit)

Make an External Hard Drive Bootable with CMD. Applies To: Windows 10/8/7. Windows Command Prompt can also be useful methods to create a bootable external hard drive in Windows 10, 8 or 7. But compared with method 1, this solution is more complex and is likely to cause a boot failure. Be cautious during this process. Format the external hard. In addition, you can easily update a USB stick or external hard drive each time an update to Mac OS X is released, as explained below; with a DVD, you have to toss the disc in the trash and start. Here is a guide on how to create a bootable external Mac hard drive to run macOS from an external hard drive. There are quite a few reasons for why you may want to be able to have an additional startup drive for your Mac. One of the main reasons is backup of your current system. Another is creating a drive for testing your Mac’s hardware. In order to make external hard drive bootable Windows 10, you need to format external hard drive at first. Step 1: Insert the external hard drive into your computer. Type cmd in the search box and right-click Command Prompt and choose Run as administrator to continue.

The simplest and quickest way to make an external hard drive bootable is to use the Windows backup software - EaseUS Todo Backup. EaseUS Todo Backup is recognized as the best system backup software as well as disk/partition clone utility that includes a highlighted feature called 'Create Portable Windows USB drive'. It's available in the 'System Clone' function. The software will clone all system files, boot files and other personalized data files to the target drive. Simply prepare your external hard drive in which you're going to make bootable, and follow the video tutorial or detailed steps below to make an external hard drive bootable in Windows 10 or other supportable OS.

To successfully make an external hard drive bootable, you need to make sure its usable space is larger than the space taken by your system. What's more, you need to delete all the partitions on the hard drive. (Luckily, with this software, you can back up all the existing files on it in advance.) The last requirement for the USB drive is that it has the same partition style as the source disk.

Video tutorial:

Detailed guide:

Step 1. Connect the external hard drive to your computer and make Windows recognize the drive. Now launch EaseUS Todo Backup and click 'System Clone'.

Step 2. The software has chosen the entire Windows 10 system partition and boot partition by default, so you just choose the external hard drive as the destination drive.

In 'Advanced options', there are three extra Windows 10 system clone features for you to choose from.

Optimize for SSD: tick this option if the destination hard disk is a Solid State Drive.

Sector by sector clone: tick this option if you wish to clone everything from the source disk including the blank space.


Create a portable Windows USB drive: tick this option so that the cloned external hard disk is able to boot normally.

Step 3. Click 'Proceed' to immediately clone Windows 10 to an external hard drive.

You should now create your own bootable hard drive with EaseUS Todo Backup software. After it's done, you can boot a computer from the external hard drive:

  • Connect the external hard drive to the computer
  • Restart the computer and press 'F2' or 'Del' to enter BIOS settings
  • In the Boot option, select the external hard drive as the new boot drive and save all the changes.
  • Exit BIOS and restart the computer, you should be able to see Windows 10 running on your new disk without any problem

In addition to being a bootable HDD/SSD/USB creator, EaseUS Todo Backup also works well in backing up or cloning hard drives, SSD, and external storage devices. With it, you can do things like migrating Windows 10 to SSD, backing up and restoring your computer hard drive, partition, files, and Outlook emails. Since data loss happens on a daily basis, it's really a wise choice to equip your computer with such backup software.

Method 2. Make an External Hard Drive Bootable with CMD

Applies To: Windows 10/8/7

Windows Command Prompt can also be useful methods to create a bootable external hard drive in Windows 10, 8 or 7. But compared with method 1, this solution is more complex and is likely to cause a boot failure. Be cautious during this process.

1. Format the external hard drive

To format a drive using cmd via Command Prompt, follow the diskpart commands below carefully. Try your best to avoid any mistakes.

Step 1. Type cmd in the search box, you can get the best match called Command Prompt. Right-click on it and choose 'Run as administrator'.

Create Bootable External Hard Drive Mac Pro

Step 2. On the Command Prompt black window, enter the following commands in the same order here:

  • X is the number corresponding to your disk. You have to replace it with the corresponding letter from your own system.
  • Press 'Enter', every time you enter your command

list disk
select disk X
create partition primary
format fs=fat32

If everything goes well, this is how your cmd screen will look like

2. Copy the Windows 10 installer files

Step1. Insert your Windows DVD into the optical drive. To open 'dism.exe' in CMD, open Command Prompt Admin (Windows + X), enter the command in the following:

cd boot
G:bootbootsect /nt60 d:

  • 'g' is your DVD drive letter
  • 'd' is your external drive letter

Step 2. Copy all files from the Windows CD to the drive using xcopy by entering the command in the following:

G:xcopy g:*.* /s/h/f d:

All those commands are used to make your external hard drive bootable. Select the bootable drive at the Windows startup, it will boot Windows immediately. If you receive a message says: 'Could not open the BCD template store. Status = [c000000f]', try the following commands to repair console to rebuild BCD or, you can watch the video to fix your boot problems (BCD problems are included).

attrib c:bootbcd –h –r –s
del c:bootbcd
bootrec /rebuildbcd

Method 3. Install Windows 10/8 on External Hard Drive with Windows Built-in Feature

Applies To: Windows 10 Enterprise/Education/Pro and Windows 8/8.1 Enterprise

Make External Hard Drive Bootable Mac Mojave

In Windows 10 Enterprise/Education/Pro and Windows 8/8.1 Enterprise, there is a built-in feature that enables you to create a Windows To Go workspace by creating an imaged version of Windows on Windows-compatible external hard drives. However, unlike EaseUS Todo Backup that is available for all Windows versions. This feature is only accessible for Windows 10 Enterprise/Education/Pro and Windows 8/8.1 Enterprise users and only certified USB drives can be made bootable.

Requirements for USB Drives:

  • Has high random read/write speeds and can run Windows workloads smoothly
  • Has been tuned to ensure they boot and run on hardware certified for use with Windows 7 and later
  • Is backed with manufacturer warranties and should continue operating under normal usage

If you are using the right Windows version and have a certified external hard drive, you can make the external hard drive bootable. (This process will format your external hard drive, back up your external hard drive in advance.)

Step 1. Download the related installation ISO file from Microsoft and connect the hard drive to your computer.

How To Make Bootable External Hard Drive Mac

Step 2. Go to 'Control Panel' and find 'Windows To Go'.

Step 3. Choose the external hard drive and click 'Next'.

Western Digital

Step 4. Click 'Add search location' to search for the ISO file.

Step 5. Select the ISO file to make the external hard drive bootable.

Create Bootable External Hard Drive

Step 6. Choose whether to use BitLocker or not. If you do, be sure you won't forget the password.

Create Bootable Mac Os On External Hard Drive

Make External Hard Drive Bootable Mac

Step 7. Click 'Create' to confirm. (Windows will format your external hard drive during the process. If there is any data you want to recover, learn how to recover data from the external hard drive here.)

How Do I Make My External Hard Drive Bootable Mac

Step 8. Wait for the process to finish. When it's done, a bootable external hard drive is successfully created.

Create Bootable External Hard Drive Mac Download

To Sum Up

Create Bootable External Hard Drive Mac Software

How To Make A Bootable External Hard Drive For A Mac With Multiple Operating Systems

Create Bootable External Hard Drive Mac Air Free

Three methods have been used to make the external hard drive bootable, which offers you different choices. Method 1 clones the system to your external disk by means of system cloning. Method 2 copies the startup file on the CD to the external disk by means of the command line. Method 3 uses Windows 10 built-in features. But using Windows 10 built-in features not only has several limitations but also may cause data loss. So if you want a simple and safe solution, choose Method 1. If you have a good knowledge base, three methods are applicable. Br the way, if your drive fails to boot, you can always refer to the video in method 2 to fix the boot problem.