If you’ve had any experience creating bootable USBs on a Mac, you’ll know the frustrations of getting it to work properly every time. Since the ISO is not a native format for macOS, the operating system doesn’t have a robust ecosystem of tools for creating ISO-based installers. The problem is worse when you narrow it down to the latest versions of macOS – Catalina and Big Sur. But before you run out and get a Windows PC for the job, you should do the research to find a suitable Mac application that can accurately create a working bootable pen drive for an ISO installation file 9 times out of 10. To help you, we’ve showcased several potential solutions for you to try.
Options to Create Bootable USB Installers on macOS Catalina and macOS Big Sur
Option 1: Boot Camp Assistant
Boot Camp Assistant is a long-time friend of Mac users, especially when it comes to installing Windows on Mac. But it’s also a great utility for burning bootable ISOs to USB without the help of third-party tools. Typically, Boot Camp will get incremental upgrades when you update your Mac to a new macOS version. Alternatively, you can manually initiate the update from Apple’s Boot Camp Assistant support page.
The advantage of using Boot Camp is obvious – it’s a native Mac app, which means you’ll be comfortable with the user interface right away. Moreover, it will allow you to go beyond creating a bootable USB and actually install Windows on your Mac. However, it also has several drawbacks. Even Apple has a list of common issues like installation failed, no response, USB space allocation problems, USB drive recognition, or specific error codes like 0xc000000f or 0xc0000225 when you try to install Windows. But if it does work for you, you’re lucky. Unfortunately, it’s not a very good idea to depend on luck for such an important job as creating USB installers, especially if you’re an IT pro and it’s part of your job.
Here’s how to do it.
The process is simple enough. Once you have the ISO file, insert the drive, launch Boot Camp Assistant and choose the option to create an install disk. When you hit Continue, you’ll be taken to a page where you can choose the ISO file. The drive information will also be displayed below it. Hit Continue again and wait for the install disk to be created. You can eject the drive once the process is complete.
Option 2: Mac Terminal
Mac Terminal can also be used to create an installer from an ISO file. This is done using the diskutil and hdiutil commands in Terminal. Both of these are native command-line utilities that you can use in tandem to format your USB drive and then burn the bootable ISO file to the formatted media. Both have very straightforward syntaxes with multiple options based on what you require. However, they come with an obvious downside.
That downside is the fact that you need to have some level of experience when working with Terminal, especially after Microsoft made it harder to do, as we’ll see later in this section. The real risk, however, is that you may inadvertently make critical changes to your system files. Even if you’re using the right commands, you may not know what to do if the system throws out an unexpected error.
Here’s how to do it.
To create an install disk using Terminal, insert the drive and run the diskutil command (followed by Enter) to identify where the USB is mounted.
diskutil list
As an example, assuming your disk is listed as /disk3, input the following command followed by Enter again:
diskutil eraseDisk MS-DOS “WIN10” GPT /dev/disk3
The above command will format the USB to the GUID Partition Table. If this fails on your hardware, replace GPT with MBR and run the command again.
The next step is to mount the ISO and move it to the drive. Check the location of the ISO file and then run this command (again, hit Enter after typing the command):
hdiutil mount ~/Downloads/Win10_1903_V1_English_x64.iso
As of April 2020, Microsoft made the install.wim file too large to fit on a normal USB formatted to FAT32. For that reason, you will need to use this workaround method.
First, move all the files from the ISO to the USB except for the .wim file:
rsync -vha –exclude=sources/install.wim /Volumes/CCCOMA_X64FRE_EN-US_DV9/ /Volumes/WIN10
You will now need Homebrew to get a utility called wimlib. These two commands will do the trick:
/usr/bin/ruby -e “$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)”
and
brew install wimlib
Once you’ve done this, create a source directory for the next step, which is to split the .wim file into bits smaller than 4GB so they won’t conflict with the FAT32 that the USB is formatted to.
mkdir /Volumes/WIN10/sources
Next, split the files and move them to the USB to join the rest of your ISO files.
wimlib-imagex split /Volumes/CCCOMA_X64FRE_EN-US_DV9/sources/install.wim /Volumes/WIN10/sources/install.swm 4000
That’s it! Easy-peasy, you say? Well, only if you’ve got the experience to do something like this.
So, what do you do if Boot Camp is a problem and you don’t have the confidence to do this in Terminal? Enter Option 3!
Option 3: UUByte ISO Editor and Why it’s Recommended
UUByte ISO Editor for Mac filled a massive gap in what users needed. Most ISO to USB utilities until there were either freeware or open-source. Neither had formal tech support and both required some level of expertise. In some cases, the interface was too complex for new users. UUByte ISO Editor for Mac was designed keeping these factors in mind.
The clean and intuitive UI was the first element that the software application brought to the table. The clear layout of core features like Burn, Edit, Extract, Copy, and Create made it easy to navigate to the appropriate section. Within each page, the sections were clearly labeled and had simple controls for various operations. This gave it a near-flat learning curve, which was rare for first-time users.
The second element was the fact that it was available in Windows and Mac variants to suit a wide range of users. The two versions worked seamlessly with their respective operating systems, yet had very similar layouts, which gave users the freedom to switch from one to another without having to learn everything all over again.
The third factor was the accuracy of its operational capabilities. Whether creating an ISO disk image from files and folders, or adding and removing files to a disk image, or burning a bootable image to a disk to create an installer, UUByte ISO Editor delivers a high rate of accuracy.
The final aspect was the intuitiveness of the software. For example, once you insert your USB drive and upload the ISO file, the system will automatically default to the required partition scheme and file system settings without the need for user input. That makes it a plug-and-play utility for creating installers, which you’ll rarely see in the vast majority of similar utilities.
So, how easy is it to create a USB installer from an ISO disk image using UUByte ISO Editor for Mac? Let’s dive into the steps.
Here’s how to do it.
How to Create a Bootable USB on Mac Using UUByte ISO Editor for Mac
In preparation, you will need to do the following:
- Get the correct ISO file for Windows from Microsoft’s website here.
- Have a USB ready with adequate space to hold the ISO file. If there’s any data on it, please make sure you back it up to another location because it will be formatted during the process that follows.
- Download UUByte ISO Editor for Mac from the official UUByte website here and install the application. You will need to register the software to unlock all features and functions, and you can do this by using the confirmation code that was sent to you by email.
Assuming all this is done, let’s look at how to create the bootable media:
- Insert the USB drive into your Mac and launch UUByte ISO Editor
- Click the Burn module on the first page
- In the inner page, you’ll see several options. Click the Browse button near the top to navigate to your ISO file and import it.
- Select the correct USB drive from the dropdown options in the second section after clicking the ‘Create a Bootable USB’ radio button.
- The partition style and file system will be automatically set so there no need to change anything there. You can now name your USB drive and hit the Burn button at the bottom. Your bootable USB drive will be ready in a few moments, after which you’ll see a success message.
Conclusion
The choice is ultimately yours. If you want a native application that’s been around for years and years, go with Boot Camp Assistant – but be ready to deal with the numerous issues that users have reported over the years. If you have the requisite experience, the Terminal method might be good for you; if you don’t, try to avoid this approach because of the risks involved. On the other hand, if you’re looking for something that’s fast, accurate, intuitive, versatile, and, above all, affordable, then UUByte ISO Editor for Mac is the obvious choice.