EnableCors attribute is not working after hosting on IIS .

Question

Cors is enabled in the web api at global level and is working fine locally, i am able to call it from any origin

but after hosting it on IIS 7.5 for testing , the cors policy again started poping up.

public static void Register(HttpConfiguration config)
       {
           // Web API configuration and services

           // Web API routes
           config.MapHttpAttributeRoutes();
           EnableCorsAttribute cors = new EnableCorsAttribute("*", "*", "*");
           config.EnableCors(cors);
           config.Routes.MapHttpRoute(
               name: "DefaultApi",
               routeTemplate: "api/{controller}/{id}",
               defaults: new { id = RouteParameter.Optional }
           );

       }

 Does it need https to work?