Install-Win8.1-in-Pendrive-UEFI

Do the following steps from a Windows System
   
On-ComandPrompt    
   

    C:\> diskpart

In the elevated command prompt, type the commands below one at a time and press Enter after each one.

    DISKPART> list disk

Make note of the Disk # (ex: Disk 4) for the USB flash drive. (see screenshot below step 5) NOTE: Substitute # in the first command with the actual disk # from step 4 above. For example: select disk 4

    DISKPART> select disk #
    DISKPART> detail disk (this is to verify that you selected the correct disk before using "clean" )
    DISKPART> clean
    DISKPART> create partition primary
    DISKPART> format fs=fat32 quick
    DISKPART> active
    DISKPART> assign
    DISKPART> list volume
    DISKPART> exit


Make note of the volume letter (ex: K) for the USB flash drive in the command prompt.

If Using a Windows 7 or Windows 8/8.1 Installation DVD

A) Insert the Windows 7 or Windows 8 installation DVD into the CD/DVD drive.
B) In the Computer window, open the DVD. (see screenshot below)
C) Select all files in it, right click or press and hold on the selected files, click/tap on Send to and the Removable Disk for your USB flash drive letter (ex: K) from step 6 above. (see screenshot below)
D) This could take a bit to copy the DVD contents to the USB.


Now Boot the USB in UEFI mode