Add your project Global.asax

• using System.Web.Routing;

protected void Application_Start(object sender, EventArgs e)
{
   RegisterRoutes(RouteTable.Routes);
}

protected void RegisterRoutes(RouteCollection routes)
{
            routes.MapPageRoute("Default",
            "index",
            "~/default.aspx");

            routes.MapPageRoute("Signup",
            "Signup",
            "~/signup.aspx");
}