How To Make WinRAR Extract .iso Files
STEP 1:
Download WinRaR and Run The Installer
STEP 2: 
Then Click "Install"
Now wait til it finishes:
STEP 3:Now this is what you should see:

Now Change them to:
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Now Click "OK"
STEP 4: 
Done.
If you have it installed follow this steps: STEP 1:Open WinRAR,
After that you should see this:
STEP 2:
Go to Options - Preferences
STEP 3: You should see this:
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Now go to the Integration Tab.
STEP 4:This is the Default:
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Now Change them to:
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DONE! Now WinRAR should act in front of .iso files as a .rar or .
zip file