private  void button_Click(object sender, RoutedEventArgs e)
    {

        Thread thread = new Thread(GO);
        thread.Start();
    }

    void GO()
    {
        Dispatcher.BeginInvoke(DispatcherPriority.Normal, (ThreadStart)delegate ()
        {

            using (EFContext _context = new EFContext())
            {
                var res = _context.User.FirstOrDefault(x => x.Email == Email.Text && x.Password == Password.Password);
                if (res != null)
                {
                    MainWindow w = new MainWindow(res.Id);
                    w.Show();
                    this.Close();
                }
                else
                {
                   IncorrectData.Visibility = Visibility.Visible;
                }
            }
        });
        }