用c#和GoDaddy发送电子邮件

我简直要疯了。我试图通过GoDaddy的服务器(smtp.secureserver.net)通过c#编写的web服务发送电子邮件，但由于某种原因它不工作。下面是我的代码:

public static void SendMessage(string mailFrom, string mailFromDisplayName, string[] mailTo, string[] mailCc, string subject, string body)
{
    try
    {
        using (SmtpClient client = new SmtpClient("smtpout.secureserver.net"))
        {
            client.Credentials = new NetworkCredential("myemail@mydomain.com", "mypassword");
            client.EnableSsl = true;
            //client.Credentials = CredentialCache.DefaultNetworkCredentials;
            //client.DeliveryMethod = SmtpDeliveryMethod.Network;
            string to = mailTo != null ? string.Join(",", mailTo) : null;
            string cc = mailCc != null ? string.Join(",", mailCc) : null;
            MailMessage mail = new MailMessage();
            mail.From = new MailAddress(mailFrom, mailFromDisplayName);
            mail.To.Add(to);
            if (cc != null)
            {
                mail.CC.Add(cc);
            }
            mail.Subject = subject;
            mail.Body = body.Replace(Environment.NewLine, "<BR>");
            mail.IsBodyHtml = true;
            client.Send(mail);
        }
    }
    catch (Exception ex)
    {
        // exception handling
    }
}

string[] mailTo = { "mytestaddress@gmail.com" };
SendMessage("myemail@mydomain.com", "Test Email", mailTo, null, "Secure Server Test", "Testing... Sent at: " + DateTime.Now);