Flush

setja i global.asax.cs
protected void Application_BeginRequest()
        {
            if (Request.Headers.AllKeys.Contains("Origin") && Request.HttpMethod == "OPTIONS")
            {
                Response.Flush();
            }

        }

    }
setja i webconfig undir system.webserver
    <httpProtocol>
      <customHeaders>
        <add name="Access-Control-Allow-Origin" value="*" />
        <add name="Access-Control-Allow-Headers" value="Origin, X-Requested-With, Content-Type, Accept,Authorization" />
        <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
      </customHeaders>
    </httpProtocol>