protected void Login_Authenticate(object sender, AuthenticateEventArgs e)
        {
            if (Session["Users"] != null) {
                var Users = Session["Users"] as List<Models.User>;
                var user = Users.Find(f => f.Email == Login.UserName && f.Password == Login.Password);
                if (user != null)
                {
                    FormsAuthentication.SetAuthCookie(user.Email, true);
                    Session.Add("LogonTime", DateTime.Now);
                    Session.Add("Admin", "true");
                    Response.Redirect("User/main.aspx");
                }
            }

            if (FormsAuthentication.Authenticate(Login.UserName, Login.Password)) {
                Session.Add("LogonTime", DateTime.Now);
                FormsAuthentication.RedirectFromLoginPage(Login.UserName, true);
                Response.Redirect("Admin/users.aspx");
            }
            else
                Login.FailureText = "Bad username or passwod";
        }
    }