private void button_Click(object sender, RoutedEventArgs e)
        {
            User User = Treatments.CreateSession();

            if (!string.IsNullOrEmpty(PassBox.Password))
            {
                bool CorrectCredentials = Treatments.CheckCredentials(PassBox.Password, User);
                if (CorrectCredentials)
                {
                    MainMenu Menu = new MainMenu();
                    Menu.Show();
                    this.Close();
                }
                else
                {
                    ErrorTBlck.Text = "Error: Wrong Password";
                }
            }
            else
            {
                ErrorTBlck.Text = "Error: No Password typed.";
            }
        }