The image files usually end in ISO or IMG. These are an actual image of the CD/DVD media as is.There are a couple steps you can take:

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  You might be able to rename it to a .ISO file and access it with Daemon or IsoBuster.
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• Burn the image file using something like Nero, burning it to DVD/CD
• Use a 3rd party tool to extract the contents of the image (like ISOBuster) and run the installation from the computer
• Use a 3rd party Virual CD mounting tool, like MSVCD for example, to mount the image to that virtual CD drive, so you can run the installation/files as if you were running it from an actual CD/DVD.
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