The first thing to understand is that image files are a messy business. There is plenty of cross-over information and functionality between image file extension types – it is easy to get confused!

Don’t be surprised if you can’t mount an .img file in Windows 10 with their default utility – it’s a common problem and this article will help.

It is important to understand not all image files are the same. Heck, not all .img files are the same. Some basics: For the term “image files” you typically see .img files and .iso file extensions and they have similar functionality and conceptually accomplish the same goal. The goal is for an image file to hold digital content, in a single file, of a file system and a its set of data. If that sentence is confusing, then maybe think of an image file this way: a zip file (but without compression).

A very quick summary explaining the difference of .img and .iso image files. An optical disc holding data is configured differently than hard drive storage space. The optical disc has data written in a linear configuration and is a digital binary copy of the ISO 9660 standard or derivative UDF standard. The ISO file extension is a single file which contains all the digital information just described.

An .img file is a digital copy of the contents of a hard drive or flash drive. Technically you can have an .img of a CD or DVD as well, but most should associate the image of a disc as ISO. An .img file is a disk image which begins with a FAT sector which is used to identify the file system and files contained inside the image file. The image file of a disc (ISO) begins with a descriptor file which describes the layout of the disc.

That last sentence is important:

If anyone searches for “burn ISO to USB” they will get pages and pages of Rufus links. However, there is a big misconception with Rufus… it doesn’t create USB CD-ROM drives!

The only thing Rufus does is take a bootable ISO file and write the data to a USB stick. Basically Rufus will extra the data on an ISO file and write it to the flash drive. You can do the same thing with WinRAR.

There is nothing magical about Rufus when it comes to “making a CD” because Rufus doesn’t make a “CD.”

If you need to make a USB CD-ROM flash drive the best solution found so far, is the Disc License drive. The Disc License drive is a blank USB CD-ROM flash drive. Using their Drive Wizard software (free), easily write ISO files to USB. The resultant drive will be a USB CD-ROM flash drive.

Before we get into Disc License technology, we do need to clear up some points about WinRAR and Rufus software. WinRAR will extract all the files contained in an ISO file and write them to your USB flash drive; however, if the ISO is bootable, WinRAR won’t write the boot code. This is where Rufus does shine. The Rufus software will write all the files contained in an ISO file along with the boot code to make your device bootable. With that said, there is a clear advantage for using Rufus over WinRAR.

Does Rufus burn any ISO file to USB? NO.

Does Rufus make your USB flash drive read-only, like a CD? NO.

If the ISO file isn’t bootable, there isn’t much [more] Rufus can offer. A non-bootable image will display an error message saying “This image is either non-bootable, or it uses a boot or compression method that is not supported by Rufus.”

Rufus is truly designed for one thing: