Change the extension, not the name of the file only! After you do this:
Show your File Extensions:
Go to the folder you have your file,
then click on Tools at the top, go down to Folder Options, then click on View tab,
scroll down and uncheck the box that says "hide file extensions for known file types",
Your file should be something like this: xxx.exe, delete the exe part (Nothing Else! and replace it with iso. Does that work?
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