[asp.net-mvc] HTTP Error 403.14 - Forbidden The Web server is configured to not list the contents

My colleagues made a URL Rewrite rule, which reduced all URLs to a StaticFileHandler; mapped to a file path at the root of my Application physical folder.

(i.e. an over-aggressive URL rewrite means that my Controllers/Actions were not working)

Check your applications' URL Rewrite rules to confirm they do what you expect.