/// <summary>Processes HTTP requests that fail authorization.</summary>
 /// <param name="filterContext">Encapsulates the information for using <see cref="T:System.Web.Mvc.AuthorizeAttribute" />. The <paramref name="filterContext" /> object contains the controller, HTTP context, request context, action result, and route data.</param>
 protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
 {
     Logout();
     filterContext.Result = filterContext.GetLogin(GetUrlLogin());
 }