Download OSFMount by PassMark Software
After Downloading OSFMount, click Mount Drive Image
Next click Mount new… (highlighted)
Next click … (highlighted)
Next click the Image you want to convert and then Open (highlighted)
Next you will see it show up in the box highlighted, click OK. (highlighted)
After clicking Ok, you will see the image in the box shown below:
Right-click the Image and select Save to Image File or Alt+I
Now, Name the Image to whatever you want (notice below in the Save As Type box and see where it will save as .iso), give it sometime and there you go!
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