SmtpClient 由于连接方在一段时间后没有正确答复或连接的主机没有反应，连接尝试失败

zhengrong822 2016-02-23 10:47:33

最近邮件发送总是提示发送失败，错误提示如下图：

代码如下：

/// <summary>  

        /// 处审核后类的实例  

        /// </summary>  

        /// <param name="To">收件人地址[di zhi]</param>  

        /// <param name="From">发件人地址[di zhi]</param>  

        /// <param name="Body">邮件[you jian]正文[zheng wen]</param>  

        /// <param name="Title">邮件[you jian]的主题</param>  

        /// <param name="Password">发件人密码[mi ma]</param>  

        public SendMailAction(string To, string From, string Body, string Title, string Password, int port, string host)

        {

            mailMessage = new MailMessage();

            mailMessage.To.Add(To);

            mailMessage.From = new System.Net.Mail.MailAddress(From);

            mailMessage.Subject = Title;

            mailMessage.SubjectEncoding = Encoding.UTF8;

            mailMessage.Body = Body;

            mailMessage.IsBodyHtml = true;

            mailMessage.BodyEncoding = System.Text.Encoding.UTF8;

            mailMessage.Priority = System.Net.Mail.MailPriority.Normal;

            this.password = Password;

            this.port = port;

            this.host = host;

        }



        /// <summary>  

        /// 发送邮件[you jian]  

        /// </summary>  

        public void Send()

        {

            if (mailMessage != null)

            {

                smtpClient = new SmtpClient();

                smtpClient.UseDefaultCredentials = false;

                smtpClient.Credentials = new System.Net.NetworkCredential(mailMessage.From.Address, password);//设置[she zhi]发件人身份[shen fen]的票据  

                smtpClient.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;

                smtpClient.Host = this.host;

                smtpClient.Port = this.port;

                smtpClient.EnableSsl = true;

                //smtpClient.Timeout = 180000;

                //smtpClient.SendCompleted += new SendCompletedEventHandler(CompletedMethod);//注册[zhu ce]异步[yi bu]发送邮件[you jian]完成时的事件[shi jian]  

                //smtpClient.SendAsync(mailMessage, mailMessage.Body);



                smtpClient.Send(mailMessage);

            }

        }