Bootable USB stick

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diskpart
list disk
select disk [#] // select disk # , usb disk number
clean
create partition primary
select partition 1
active
format fs=ntfs // fs=fat32 // fs=fat32 quick
assign
exit
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If your server platform supports Unified Extensible Firmware Interface (UEFI), you  should format the USB flash drive as FAT32 rather than as NTFS. To format the partition as FAT32, type format fs=fat32 or fs=fat32 quick, and then Enter.