Asp.net 如何注册路由区域

我创建了MVC应用程序，它有三个不同的区域.(管理员、用户、新闻)

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
            namespaces: new[] { "TestMvcApplication.Controllers" }
        );
    }
}

这是我的行政登记.cs文件:

    namespace TestMvcApplication.Areas.Admin
{
    public class AdminAreaRegistration : AreaRegistration
    {
        public override string AreaName
        {
            get
            {
                return "Admin";
            }
        }

        public override void RegisterArea(AreaRegistrationContext context)
        {
            context.MapRoute(
                "Admin_default",
                "Admin/{controller}/{action}/{id}",
                new { controller = "Home", action = "Index", id = UrlParameter.Optional },
                namespaces: new[] { "TestMvcApplication.Areas.Admin.Controllers" }                
            );
        }
    }
}

最后，这是我的Global.asax.cs文件内容:

namespace TestMvcApplication
{
    // Note: For instructions on enabling IIS6 or IIS7 classic mode, 
    // visit http://go.microsoft.com/?LinkId=9394801

    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            WebApiConfig.Register(GlobalConfiguration.Configuration);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
            AuthConfig.RegisterAuth();
        }
    }
}

我的网站主页已完全加载，并且运行正常.但管理员主页或其他区域未按路径检测，我给出了以下错误消息:

Server Error in '/' Application.
The resource cannot be found.
Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable.  Please review the following URL and make sure that it is spelled correctly.

Requested URL: /Admin/Home

我怎样才能解决这个问题？