private void AddUser(object parameter)
        {
            log.Debug("Add user button");

            if (Password != Confirm)
            {
                NotificationProvider.Error("New user error", "Password does not match the confirm password.");
            }
            else
            {
                try
                {
                    if (UserLogin.AddUser(UserID, Password))
                    {
                        NotificationProvider.Info("New user added", String.Format("Username: {0}", UserID));
                        NewUserWindow.Close();
                    }
                    else
                    {
                        NotificationProvider.Error("New user error", "Username already exist.");
                    }
                }
                catch
                {
                    NotificationProvider.Error("New user error", "Please fill the Username and Password fieleds.");
                }
            }
        }