private void Send_Click(object sender, EventArgs e)
        {
            try
            {
                Output.Text = string.Empty;

                _emailSender.ReadFile();
                _emailSender.SendEmail();

                Output.Text = "Sent email with body: " + Environment.NewLine + _emailSender.MessageBody;
            }
            catch (Exception ex)
            {
                Output.Text = ex.ToString();
            }
        }