通过SMTPClient获得错误发送邮件 - 无法从传输连接中读取数据

Question

使用SMTPClient发送电子邮件时，我会遇到“无法从传输连接中读取数据”的错误。当我在Visual Studio中运行此问题时，不会发生错误。该错误仅在IIS中运行时发生。以下是我的代码：

            System.Net.ServicePointManager.Expect100Continue = false;
            System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;
            ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(IgnoreCertificateErrorHandler);

            SmtpClient SmtpServer = new SmtpClient(_serviceSettings.SMTPServer, _serviceSettings.SMTPPort);
            SmtpServer.Port = _serviceSettings.SMTPPort;
            SmtpServer.UseDefaultCredentials = false;
            SmtpServer.Credentials = new System.Net.NetworkCredential(_serviceSettings.SMTPUser, _serviceSettings.SMTPPass);


            MailMessage mail = new MailMessage();
            mail.From = new MailAddress(_serviceSettings.SMTPUser);
            mail.To.Add(_serviceSettings.SMTPErrorTo);
            mail.Subject = "Error Message";
            mail.Body = errorMessage;

            SmtpServer.EnableSsl = _serviceSettings.SMTPUseSSL;

            SmtpServer.Send(mail);

Answer 1

最终是SMTP服务器的问题。集群中的电子邮件服务器之一是遇到问题。