How to create a bootable Windows 10 USB on Mac

How to create a bootable Windows 10 USB on Mac

The last release of Mac OS doesn't have the option to create a bootable USB from Bootcamp like previous versions, and it is a problem because that require uses other tools.

I am updating this post today Dec 12, 2018. The reason is that I was only using UNetbootin to create the bootable USB, I will leave guide as a second method since it still working, and I will explain to you how you can create the bootable Windows USB without extra software.

The first step for both methods requires to format your USB device to NTFS, this is the default filesystem, alternative you can use ExFAT but the installation could fail.

Format USB to ExFAT (Under your own risk)

In order to boot from the USB, you need to format the USB to ExFAT, you can do it using Disk Utility (it comes with MacOS).

This step is the same for both methods. You need to show all the devices in Disk Utility" before to start the process.

disk-utility-show-all-devices

Select your USB device in the list (not the partition), right click and then click on the Erase option:

disk-utility-erase

In the next screen make sure you select these two options:

  • Format: ExFAT
  • Scheme: Master Boot Record

Click the Erase button.

disk-utility-windows-settings

If for some reason it fails, probably is because MacOS still using the USB, just repeat the steps, but if you see a screen similar to above screen is because the operation is successful.

disk-utility-windows-success

Format USB with the terminal

You also can format the USB from the terminal, but you have to take care to use the correct device because, if you use the wrong name you will lose everything.

With this command you can list the device on MacOS:

diskutil list

This is an example, my USB is the disk2:

disk-util-list

This command is to format the USB, the last parameter is the the USB:

diskutil eraseDisk ExFAT "WINDOWS10" MBRFormat disk2

diskutil-format-usb


Copy Windows files to USB - Method 1

This process is very easy doesn't require to install other software, and they are just a few steps:

Open Windows ISO

Just double click on the ISO image, MacOS mount the image automatically.
Windows-ISO

Copy files

Now you only need to copy the files and paste them to the USB.

  • Command + A Select all files.
  • Command + C Copy files.
  • Go to your USB Command + V paste the files.

copy-windows-files

This process could fail if you are using a USB with FAT32 because the file install.win is over 4GB, if this is the case try to open the terminal and copy paste the files from there (no always works. Try to follow the instructions to format the USB in ExFAT, NTFS works for some BIOS).

daisy-disk-windows-usb

This is the command to copy the files from the ISO to the USB:

cp -rp /Volumes/CCCOMA_X64FRE_EN-US_DV9/* /Volumes/WINDOWS10/

And that is all, now you can try boot from the USB.


UNetbootin - Method 2

I will show you how you can use UNetbootin to create a bootable USB, it can be used no only for Mac but for Windows and Linux distributions too.

UNetbootin is free software and it is also available for Windows and Linux.

Check the path name of your USB Disk.

Always in Disk Utility, select the new partition that we created in the previous step, and click on the information button, it will give you the information about the new partition.

Disk Utility USB Information

You also can use the terminal and the command diskutil to see the list of drives:

diskutil list

Download UNetbootin:

brew cask install --appdir="/Applications" unetbootin

Makes the USB booteable

Open UNetbootin and you only need select 3 options:

  • Diskimage and ISO
  • Now we need open the ISO Windows image that is on our computer.
  • Select your USB device on UNetbootin.
  • Click on the OK, button and wait to the process end it will take a time.

UNetbootin Windows

NOTES:

  • I tested other tools like dd and Etcher but they are not working because Windows requires extra steps, for the moment this is the only easy tool that I know that works if you are on Windows try Rufus.
  • Some users reported that UNetbootin is not working, if after to format the USB drive and change the block size is not working for you try another Drive with enough space.