System.IO.IOException：无法从传输连接读取数据：net_io_connectionclosed

Question

我正在尝试通过Gmail向客户发送邮件列表给500个客户，问题是它只发送89然后我收到以下错误：

  

System.IO.IOException：无法从传输中读取数据   连接：net_io_connectionclosed

当我将500发送到本地接收时，我的代码确实有效。

我已经阅读了很多帖子，客户说她每天限制2000封电子邮件，所以我不知道问题是什么。

任何人都可以对此有所了解。

代码

var emailMessage = new MailMessage();
                emailMessage.To.Add(new MailAddress(emailRecipicant,customerName.Trim()));
                emailMessage.From = new MailAddress(smtpEmail);
                emailMessage.Subject = $"{emailSubject}";
                emailMessage.Body = string.Format(body);
                emailMessage.IsBodyHtml = true;



                using (var smtp = new SmtpClient())
                {
                    smtp.UseDefaultCredentials = false;
                    var credential = new NetworkCredential
                    {
                        UserName = smtpUsername,
                        Password = smtpPassword
                    };
                    smtp.Credentials        = credential;
                    smtp.Host               = smtpHost;
                    smtp.Port               = Convert.ToInt32(smtpPort);
                    smtp.DeliveryMethod     = SmtpDeliveryMethod.Network;
                    //smtp.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
                    //smtp.PickupDirectoryLocation = "C:\\Users\\pht_000\\Desktop\\Customers\\Email\\PickUp\\";
                    smtp.EnableSsl          = false;
                    smtp.Send(emailMessage);
                }

上述void方法通过以下

循环

foreach (var recipicant in model.ToList())
                    {
                        string emailRecipicant = recipicant.Email;
                        string emailSubject = recipicant.Subject;
                        string message1 = recipicant.Message;
                        string encryptedLink = recipicant.EncryptedEmail;
                        string customerName = recipicant.Contact;
                        SendEmail(emailRecipicant, emailSubject, message1, encryptedLink, customerName);

                        counter++;
                    }