![Windows Windows](/uploads/1/2/5/8/125846580/646187497.jpg)
How to Create a Mac OS X USB Boot Drive on Windows Kevin Muldoon. If you search online for 'OS X DMG Download' you will find many websites that host the DMG file for your Mac's operating system.
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Boot Camp Assistant User Guide
Newer Mac computers use a streamlined method to install Windows on your Mac. To find out whether your Mac uses this method, see the Apple Support article Install Windows 10 on your Mac with Boot Camp Assistant. If your Mac is an older model, follow the instructions in Install Windows on your older Mac using Boot Camp instead.
What you need
- The keyboard and mouse or trackpad that came with your Mac. If they aren’t available, use a USB keyboard and mouse.
- A full-installation, 64-bit version of Windows 10 on a disk image (ISO file) or other installation media.You can download a Windows 10 Disc Image (ISO File) from Microsoft.
- Sufficient free storage space on your startup drive. For information about the amount of free space needed, see the Apple Support Article Install Windows 10 on your Mac with Boot Camp Assistant.
Before you begin
Before you install Windows, make sure you back up important files.
You can use Time Machine or any other method to back up your files. For information about backing up files, see Back up your files with Time Machine and Ways to back up or protect your files.
Perform the installation
On your Mac, do the following steps in order.
Step 1: Check for software updates
Before you install Windows, install all macOS updates.
- On your Mac, log in as an administrator, quit all open apps, then log out any other users.
- Choose Apple menu > System Preferences, click Software Update, then install all available macOS updates.If your Mac restarts after installing an update, open Software Update again to install any additional updates.
Step 2: Prepare your Mac for Windows
Boot Camp Assistant prepares your Mac by creating a new partition for Windows named BOOTCAMP and downloading the Boot Camp support software.
Important: If you’re using a portable Mac, connect it to a power source before continuing.
- On your Mac, open Boot Camp Assistant , located in /Applications/Utilities.
- At the Introduction screen, click Continue.The system is checked for total available disk space. Older Time Machine snapshots and cached iCloud files are removed to make space for Boot Camp. This process may take a long time to complete (you can click the Stop button to skip this process).
- At the Install Windows step, click Choose, then select the Windows ISO image.
- Specify a partition size by dragging the divider between the macOS and Windows partitions.
- Click Install.
When this step is complete, the Windows installer starts.
Step 3: Install Windows
- In the Windows installer, follow the onscreen instructions.When the installation is finished, your Mac automatically restarts using Windows.
- Follow the onscreen instructions to set up Windows.
Step 4: Install Boot Camp on Windows
After installing Windows, Boot Camp drivers that support your Mac hardware start installing.
Note: If the support software doesn’t install automatically, you need to install it manually. For instructions, see the Apple Support article If the Boot Camp installer doesn't open after using Boot Camp Assistant.
- In the Boot Camp installer in Windows, follow the onscreen instructions.Important: Do not click the Cancel button in any of the installer dialogs.If a message appears that says the software you’re installing has not passed Windows Logo testing, click Continue Anyway.You don’t need to respond to installer dialogs that appear only briefly during installation, but if a dialog asks you to install device software, click Install.If nothing appears to be happening, there may be a hidden window that you must respond to. Look behind open windows.
- When the installation is complete, click Finish.
- After your Mac restarts, follow the instructions for any other installers that appear.
See alsoGet started with Boot Camp on MacTroubleshoot Boot Camp Assistant problems on MacApple Support website: Boot Camp Support
I’ve been using a late 2013 Retina Macbook Pro as my primary computer for almost two years. It meets all my needs in my day job and is light enough to carry everywhere even while flying around for work.
While I love the time flying affords to switch offline and catch up on some well deserved gaming, mobile gaming can be bit bland and Mac OS X doesn’t run my favourite games like Skyrim without some fairly unreliable and poorly performing hacks via Wine.
But what about Bootcamp? I was in a very limited place, the 256GB SSD quickly fills up and I couldn’t spare the space to partition and install Bootcamp Apple’s way.
Enter the Samsung Portable SSD T1, this speedy little drive is small enough to hang off the side of my Macbook without getting in the way and a bump or two won’t damage it.
Unfortunately Windows refuses to install to any USB based storage which has historically been far too slow to run a fully fledged operating system.
But that’s no issue for the T1 which by Samsung’s own estimates can reach up to 450MB/s. It’s more than fast enough to run Windows as if it were running directly on the internal drive.
Luckily with the power of virtualisation it’s easy to bypass these pesky limitations and get Bootcamp running entirely off the external USB SSD drive without making any changes to the internal SSD.
Read on to find out how!
What you’ll need:
You’ll need a few things to complete this guide:
- A Mac which supports booting from a USB Device (see Apple Support: Mac computers that support Windows 10)
- A USB 3.0 SSD similar to the Samsung T1 (a flash storage device will not be fast enough)
- A spare USB drive with a minimum of 2GB of storage to copy the Bootcamp Drivers over to Windows.
- Basic understanding of VirtualBox and installing Windows.
Download Windows 10 Installation
Windows 10 is available to download from Microsoft and allows a grace period to license the installation. Windows 10 can be purchased from the Microsoft Store.
Follow the prompts to download Windows 10 installation disk.
The download is 3.7GB so it may take some time, the next steps will prepare your system to install Windows 10 to the USB SSD.
Download Bootcamp Software for Windows 10
Apple offer a prepackaged driver installation for Bootcamp.
Thanks to Reddit user sadalhayat for identifying this link.
Once this has downloaded copy it to a spare USB drive separate from SSD you will be using to install Bootcamp. Save this for later.
Mac OS X cannot write to the Windows drive out of the box. For this reason you will need to use a separate drive to copy the Bootcamp Software into the new Bootcamp Installation.
Install VirtualBox
Are you wondering why VirtualBox is the next step? Don’t worry, we’re taking advantage of the virtualisation technology to kick start the installation of Windows 10.
We will be using VirtualBox to mount the USB drive as a virtual hard disk inside the Virtual Machine. This bypasses the limitations imposed by the Microsoft Installer preventing us from installing Bootcamp the Apple way.
Download and Install VirtualBox
If you don’t already have VirtualBox, it can be downloaded from their website. Once you have downloaded the package, use the installation package to get up and running with VirtualBox.
Identify your USB Drive’s device location
Open up the Terminal and type:
This command will list all the connected drives on your computer. Browse through the list until you find your storage device.
The text highlighted red “/dev/disk2” is the information we need. This information will tell VirtualBox exactly which storage device it needs to access.
Please note this information may be different on your machine. Read the list carefully to match the address of your USB SSD.
Disconnecting Mac OS X from the USB SSD.
Before we connect VirtualBox to our USB SSD you will need to completely unmount the SSD from Mac OS X to allow VirtualBox full access to the USB SSD.
This can be done by searching for Disk Utility in Spotlight then
- Choosing the External USB Device
- Choosing Eject in the top Menu
Create a Virtual Disk mapping to the USB Drive
This is where the magic starts. We will be using VirtualBox to mount the USB SSD as a normal hard disk in order to trick the Windows 10 installer into thinking it is using a normal hard drive.
First we need to create a Virtual Disk File for VirtualBox so it knows what storage device we are accessing.
Below is the command we will be modifying to create the Virtual Disk file
You can copy the entire command with the exception of the last part “/dev/diskX” which will need to be changed to the drive number you identified in the previous step.
In my case it is “/dev/disk2”.
Installing Windows 10 to the USB SSD via VirtualBox
Now that we have everything organised we can start the installation of Windows 10 via VirtualBox.
We will need to give VirtualBox elevated permissions to access our handy bootcamp.vmdk file.
In your terminal type:
This will force VirtualBox to run as the root user and have permission to access the USB SSD.
Creating Virtual Machine
In VirtualBox choose “New” and type “Windows 10 Bootcamp” and click Continue.
Change Memory to “512” MB and click Continue.
On the Hard Disk screen choose “Use an existing virtual hard disk file” browse to your home directory and select the newly created “bootstrap.vmdk”.
Installing Bootcamp, from a Virtual Machine
Now that we have scaffolded the Virtual Machine, connected the hard drive and downloaded Windows 10, it is time to install Windows 10 onto our shiny new USB SSD.
Back in VirtualBox we will need to mount the Windows 10 Installation ISO into the virtual DVD drive.
- Open the Virtual Machine’s Settings Panel.
- Select the Storage tab on the top of the Settings Panel.
- Select the Empty DVD Icon.
- Select the CD Icon next to the Optical Drive, Choose Virtual Optical Disk File and select the Windows 10 ISO file.
- Select OK to save the new settings.
Run the Normal Windows 10 Installation
Follow through the standard screens to begin the Windows 10 installation.
Clicking next and agreeing to the terms and conditions is all you really need to do here except for the following points:
When you meet the installation type screen, select “Custom”.
When you are asked where to install Windows, just delete any existing partitions and select “Next”.
Don’t worry, Windows can only see the USB SSD drive you assigned by VirtualBox, your Mac’s existing partitions are not accessible here.
Important! Don’t let windows restart!
This is the most crucial step to successfully installing Bootcamp on an external USB 3.0 SSD
When Windows 10 is restarting, make sure you prevent Windows restarting inside the Virtual Machine and completing the installation.
- When you see the VirtualBox BIOS screen select the Red Close Button
- Choose “Power off the machine”.
- Choose OK to power off the Virtual Machine.
That’s enough Virtualisation!
Now that we’ve completed the first phase of the Windows 10 installation, we don’t need to use VirtualBox anymore.
This completes all the steps required on the Mac OS X side of the installation.
Reboot your Mac into Windows
It’s now time to restart your Mac and boot into Windows 10. Power off your Mac and hold the Option key until disk icons appear onscreen.
Let Windows 10 install
![Windows Windows](/uploads/1/2/5/8/125846580/609765542.png)
If everything went well Windows 10 should start booting and begin the initial installation.
Just follow through the screens and fill in your details as required.
Windows 10 may reboot during the installation. If this occurs, make sure you press the Option Key and select the Boot Camp Drive to continue the installation.
Install Bootcamp Software
Plug in the spare USB Drive we copied the Bootcamp Software to earlier and run “AppleBCUpdate.exe”.
This will start the Bootcamp installation software to install drivers for the Apple Keyboard and Mouse, Wireless, Graphics and other devices in your system.
That’s it!
If everything went according to plan you should now be able to boot directly into Windows 10 whenever the USB SSD is connected to your computer!
My experience has been rock solid, and I can enjoy all the benefits of running Bootcamp on my Mac to run Windows Applications and Games without sacrificing the valuable storage space of the internal SSD.
Did you find this article helpful? Let me know in the comments section below!
Keep in mind Microsoft and Apple never intended for you to run Bootcamp this way. Make sure you never disconnect the USB SSD from your system while Windows is running!