Insert your USB flash drive and enter the following commands at a command prompt:
(Note: The instructions below assume that your USB flash drive will be seen as disk 1. Confirm the disk number of the USB drive first by using the “list disk” command before the “select disk” command below. If you select the wrong disk you will wipe the wrong drive…possibly your hard disk drive.)




diskpart
select disk 1
clean
create partition primary
select partition 1
active
format fs=fat32
assign
exit

The final step is to copy the files from the bootable ISO to the USB key. Mount the ISO using a program such as Virtual CloneDrive. Use Xcopy to copy the files from the ISO to the USB key. The command line below assumes that D: is the drive letter where the bootable ISO is mounted and E: is the drive letter for the USB key.

xcopy d:\*.* /e/f e:\