Hi, in this video, I will show how to create Windows bootable USB flash drive from ISO image with Rufus. 
First, download Rufus.
Open web browser to https://rufus.akeo.ie
Scroll down to download section
and click on the latest version to download.
Next, click the file to run Rufus.
Then, connect the USB flash drive and select it from the drop-down 'Device' option.
If you want to create bootable UEFI, you have to select 'GPT partition for UEFI computer'.
Otherwise, you can use the default value.
For file system and cluster size options, you can use default values. 
The program will modify these values after we select image file.
And make sure that the check box 'Create a bootable disk using...' is checked 
and select 'ISO image'.
Next, click the browse icon next to it. 
And browse to the ISO image and click 'Open'.
Then, click 'Start' to begin
You will be asked to confirm that all data on the USB flash drive will be deleted. 
Click 'OK' to continue.
In this example, Rufus took about 20 minutes to create Windows 8.1 bootable USB flash drive. 
When the program finishes, you can eject the flash drive and use it to install Windows on any computer.
To boot from the flash drive, you may have to configure 
boot order in BIOS.
Or you can select from boot menu if your BIOS has the option.
As in this example of MSI mainboard which boot menu can be accessed by press 'F11'. 
Then, I can select my SanDisk Cruzer Fit. 
If you want to boot as UEFI, you have to select that option.
And it will boot from my USB flash drive right through Windows 8 Setup page.
So that's the end of this video.
 I hope it be useful to you. 
If you have any question, please post below.
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Thank you for watching.
Goodbye. 
