HWIT-NetworkCredential basicCredential

1. 在HWIT以SmtpClient發送內部郵件OK，外送郵件需驗證      
        public static void SendMail(string 人, string 信)
        {
            //------- 認證
            SmtpClient smtpClient = new SmtpClient();
            MailAddress from = new MailAddress("csjou@mail.hwc.edu.tw");
            smtpClient.Host = "mail.hwc.edu.tw";
            //NetworkCredential basicCredential =
            //    new NetworkCredential("csjou", "xxxxxxxx");
            //smtpClient.UseDefaultCredentials = false;
            //smtpClient.Credentials = basicCredential;
            // Set destinations for the e-mail message.
            MailAddress to = new MailAddress(人);
            // Specify the message content.
            MailMessage message = new MailMessage(from, to);
            message.Body = 信;
            // Include some non-ASCII characters in body and subject.
            string someArrows = new string(new char[] { '\u2190', '\u2191', '\u2192', '\u2193' });
            message.Body += Environment.NewLine + someArrows;
            message.BodyEncoding = System.Text.Encoding.UTF8;
            message.Subject = "test message 1" + someArrows;
            message.SubjectEncoding = System.Text.Encoding.UTF8;
            //string 附檔 = @"C:\Users\Public\Pictures\Sample Pictures\Desert.jpg";
            //Attachment 附件 = new Attachment(附檔);
            //message.Attachments.Add(附件);
            smtpClient.Send(message);
            Console.WriteLine("Sending message... press c to cancel mail. Press any other key to exit.");
            string answer = Console.ReadLine();
            // If the user canceled the send, and mail hasn't been sent yet,
            // then cancel the pending operation.
            if (answer.StartsWith("c") && mailSent == false)
            {
                smtpClient.SendAsyncCancel();
            }
            // Clean up.
            message.Dispose();
            Console.WriteLine("Goodbye.");
        }
2.

3. 解除紅字註解(加入個人帳號、密碼驗證)，可以寄出外送郵件