For now, you can use the following steps to create a USB Windows 10 flash drive installer.ĭownload the Windows 10 October 2018 Update ISO file from the Microsoft website Download Windows 10 Disc Image (ISO File). So, Apple could fix this problem by changing to Boot Camp Assistant to format the USB flash drive as ExFAT instead of FAT32. Mac computers running High Sierra or Mojave may be able to boot from USB flash drives that are ExFAT formatted. Here are three potential ways to create the USB installer. I have found that after upgrading to High Sierra, my 2013 iMac could boot the Windows 10 installer from a ExFAT formatted USB flash drive.