Creating a UEFI bootable Windows installer USB stick or HDD should be easy these days, but for whatever reason it remains one of those awkward things to do.

Consequently, I've put together some instructions for creating a UEFI bootable USB installer from a Windows installation ISO.

The first part of this trick is to realise that in order to be UEFI bootable, the USB needs to be formatted in FAT32 - this means tools like the otherwise-excellent Rufus are going to have issues, as they try to default a Windows installation to being NTFS.

Firstly, we need to make a partition on the drive we're going to be using by running the command ine DISKPART tool. To do this enter the following commands: (where the X below is the numerical value for the target disk in your system)

diskpart
list disk
select disk X
clean
create partition primary
format quick fs=fat32
active
exit

Make sure the disk has a drive letter (if not, use the command line "assign" command to give it one) ...and that's the hard bit done. Finally, we just need to copy the contents of our Windows installation ISO to the newly created partition. Use Windows Explorer to mount the ISO as a CD-drive, and the use the XCOPY command line tool to copy all the files from the ISO to our destination disk. (in the example below, D: is the letter given to our "pretend" CD-drive, containing the Windows ISO, and E: is the drive letter of our destination disk)

xcopy d:\* e:\ /s /e

The XCOPY command will take an absolute age to run. Don't think it's crashed, just leave it (for a good 10 - 15 minutes), then when it's finished, you're good to go. One EUFI bootable installer disk created!