ERROR 404.3 Not Found for JSON file | CodeAsp.Net

While working with a json file today I got the following error from server:

HTTP Error 404.3 - Not Found
The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map.

The solution was to add the mime type in the web,.config like this:

 <system.webServer>
    <staticContent>
      <mimeMap fileExtension=".json" mimeType="application/json" />
    </staticContent>
  </system.webServer>