Create Windows 10 bootable usb on Mac

I don't recommend this ancient tool,as it doesn't help.

https://download.cnet.com/Apple-Boot-Camp-Support-Software/3000-18513_4-93144.html

I think the best ways to crate an effective Windows 10 bootable USB for Mac Catalina is these.

https://www.wikihow.com/Make-a-USB-Bootable

https://www.uubyte.com/create-windows-10-bootable-usb-on-macos-catalina.html

• What is the year/model of your Mac (do not post the serial number)? Check under About This Mac.
• What is the current macOS version?
• Macs after 2015 do not need a USB installer. They use an internal partition called OSXRESERVED.
• W10 1903 and later ISOs from Microsoft have a larger-than-4GB install.wim, which does not work with a FAT32 partition/disk. There are some fixes in macOS Catalina and Mojave for this specific issue.
• See the following links for reference.
  • Boot Camp - Official Apple Support
  • Install Windows 10 on your Mac with Boot Camp Assistant - Apple Support
  • Boot Camp Assistant User Guide for Mac - Apple Support

Does the PC boot using UEFI or legacy MBR? If the PC can be configured to boot using UEFI, then it is easy to make a bootable Windows USB installer. Erase the USB drive with a FAT32 partition. I don't recall if it matters whether it is a MBR partition or GUID partition.

Double-click a Windows installer .iso file to mount it on macOS. Then select all the files on the mounted volume and copy them to the USB drive. As long as the Windows installer doesn't include a file larger than 4GB this should work. I've used this multiple times for Win7 and older versions of Win10. I haven't tried this with the latest version of Win10.

If the Win10 installer has a 4GB or larger file, then you may be able to format the drive as exFAT and use the rEFInd boot manager to boot the USB drive.

Edit: This only works for installing Windows on a non-Mac computer. Otherwise you need to use Bootcamp Assistant to create the bootable Win10 installer for a Mac.

Reading the Rufusdownload site, I think you need to run Windows on the Mac in Bootcamp to run Rufus.

Difficult to follow, the site seems to be written by non-english speaker.

@hhzk388 you will learn that free and dubious apps are less available on Mac

hhzk388 wrote:

Boot camp assistant keeps saying not enough disk space. actually, it is 64G USB

FWIW, I just created a bootable Windows 10 installer to a USB flash drive using Boot Camp Assistant as per the link I posted. You might want to try a different flash drive.

Did you happen to read the original post? The OP is trying to create a Windows 10 installer for his/her mother's broken PC. And according to the title, he/she is running Catalina.

Also, was trying on a 64GB drive.

dialabrain wrote:

Did you happen to read the original post?

Yes. And the intent was to point out that in some cases BC Assistant will not support a connected USB, if used. 😉

Any PC using WMCT is a much better method than any method available on a Mac. Rufus and Unetbootin are likely to work.

The OP is trying to create a Windows 10 installer for his/her mother's broken PC. And according to the title, he/she is running Catalina.

Catalina is very strict on externally connected devices compared to older versions. 2014 and older Macs allow a separate USB Installer creation step, unrelated to partitioning the drive to install Windows.

Also, was trying on a 64GB drive.

An installer created on a Mac may not work on a PC.

As I noted in my post, I had no problem creating a Windows 10 bootable installer on Catalina using Boot Camp Assistant. Whether it boots a Windows machine I haven't checked. However, that wasn't the user's question. They were having a problem creating it in the first place.

We may never know unless the user replies.

hhzk388 wrote:

Generally, the process won't get started. It keeps saying not enough disk error even with another USB.

If the USB is formatted as FAT32, it will not work. It must be formatted as exFAT, by BC Assistant.

Model is: MBP 2013 Late

macOS 10.15.1

Please update macOS to 10.15.3 and retry. There are known bugs in formats (FAT32 vs exFAT) in Mojave and Catalina. Mojave 10.14.6 has all the correct patches. Catalina has been slow in catching up.

No chance.

Dont PC's have internet recovery like Macs? Or a recovery partition?

See: https://www.windowscentral.com/how-create-windows-10-installer-usb-drive-mac

Ok some chance!

Boot Camp has not been updated Since 2016,that meaning it has some bugs,i don't think that is a good idea.And Rufus works for people who use Mac?