routes.MapRoute(
    name: "Default",
    url: "{action}/{path}",
    defaults: new { controller = "Home", action = "Index" }
);

routes.MapRoute(
    name: "Default",
    url: "{action}/{path}/{extension}",
    defaults: new { controller = "Home", action = "Index" }
);

routes.MapRoute(
    name: "Default",
    url: "{action}/{path}.{extension}",
    defaults: new { controller = "Home", action = "Index" }
);