Error when I add "RegisterRoutes" in Global.asax

[Vo]

Help me,

I create project webApplication and add :

<telerik:RadEditor ID="radContact" Skin="Default" runat="server" Height="150px" Width="100%"
                                        ToolsFile="~/App_Data/ToolsFileSmall.xml" DialogHandlerUrl="~/Telerik.Web.UI.DialogHandler.axd">
                                        <Content>
                                        </Content>
                                    </telerik:RadEditor>

and add "RegisterRoutes" in Global.asax:

void Application_Start(object sender, EventArgs e)
        {
            // Code that runs on application startup
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
           RegisterRoutesDemo(RouteTable.Routes);
        }
        private void RegisterRoutesDemo(RouteCollection routes)
        {
            routes.MapPageRoute("chitiet_sanpham", "san-pham/{productName}/{ProductId}", "~/ProductDetail.aspx");
            routes.MapPageRoute("chuyenmuc_sanpham", "chuyen-muc/{categoryName}/{CategoryId}", "~/ProductCategory.aspx");
            routes.MapPageRoute("store", "{account}", "~/StoreOwn.aspx");
            routes.MapPageRoute("register", "dang-ky/dang-ky-gian-hang", "~/Registion.aspx");

            routes.MapPageRoute("home", "", "~/Default.aspx");
        }

Then I run project error Editor. You can help me fix error. Thanks