无法连接到远程服务器C＃-Godaddy

Question

我正在尝试使用SMTP（GODaddy）从Web API发送邮件。未能发送邮件并返回异常，如下所示

代码：

 public void SendMail()
        {
            try
            {
                MailMessage mail = new MailMessage("support@abc.com","toMail");
                mail.Subject = "Subject";
                mail.IsBodyHtml = true;
                mail.Body = "this is email body";

                SmtpClient client = new SmtpClient("relay-hosting.secureserver.net");
                client.DeliveryMethod = SmtpDeliveryMethod.Network;
                client.UseDefaultCredentials = false;
                client.EnableSsl = true;
                client.Credentials = new System.Net.NetworkCredential("support@abc.com", "****");
                client.Port = 25;

                client.Send(mail);
            }
            catch (SmtpFailedRecipientException Ex)
            {
                Ex.FailedRecipient.ToString();
            }
        }

谁能帮我解决这个问题。