尝试使用 SmtpClient 发送电子邮件时出现“达到错误限制”

Question

当我尝试使用 C# 代码发送邮件时，我收到“服务不可用，正在关闭传输通道。服务器响应为：达到错误限制”。

try
{
    MailMessage emailMessage = new MailMessage();

    emailMessage.Subject = "smth subject";

    messages = string.Empty;

    string serverName = System.Environment.MachineName;
    string serverIpAddress = Dns.GetHostAddresses(Environment.MachineName)
                                .First(ip => ip.AddressFamily == AddressFamily.InterNetwork).ToString();

    string serverNameWithDetails = Settings.Default.ServiceDisplayName + " (server's name: " + serverName + ", server's ip address: " + serverIpAddress + ")";

    emailMessage.IsBodyHtml = true;
    emailMessage.Body = "smth body";
    emailMessage.From = new MailAddress(config.SmtpUser);
    emailMessage.To.Add("myAddress@aaa.com");

    // Set encoding
    emailMessage.HeadersEncoding = System.Text.Encoding.UTF8;
    emailMessage.BodyEncoding = System.Text.Encoding.UTF8;

    SmtpClient smtpClient = new SmtpClient(config.SmptHost, config.SmptPort);

    NetworkCredential smtpUserInfo = new System.Net.NetworkCredential(config.SmtpUser, config.SmtpPassword);
    smtpClient.UseDefaultCredentials = false;
    smtpClient.Credentials = smtpUserInfo;

    smtpClient.Send(emailMessage);

    EmailSent = true;
}
catch (Exception e)
{
    log.ErrorFormat("The following error occured while building and sending the email: {0}", e.Message);
}

所以 e.Message 是上面写的错误，但我找不到有关此错误消息的任何信息。 当smtpClient.Send(emailMessage); 行被执行时，它进入catch 部分。 谁能帮我？ 对不起我的英语不好。

Answer 1

根据我的经验

服务不可用，正在关闭传输通道。服务器响应是：达到错误限制

如果您尝试发送大量电子邮件，就会被解雇 - 听起来很合乎逻辑:-)

棘手的部分是某些 ISP 的限制可能非常低（每小时 20 - 500 封不同的邮件），如果您将发件人声明为未注册的电子邮件，则在邮件服务器上，限制可以为 0 ，然后触发这种错误信息。

我的意思是：使用在邮件服务器上注册的电子邮件，并注意限制，在某些情况下，只需在调试时运行代码即可达到限制。

Answer 2

试试这个..

using System.Net;
using System.Net.Mail; 
string to = strSidMail;
string from = "rajeeshmenoth@wordpress.com";

MailMessage message = new MailMessage(from, to);
message.Subject = txt_subject.text;
message.Body = mailbody;
message.BodyEncoding = Encoding.UTF8;
message.IsBodyHtml = true;
SmtpClient client = new SmtpClient("smtp.gmail.com", 587);
System.Net.NetworkCredential basicCredential1 = new
System.Net.NetworkCredential("yourgmail id", "Password");
client.EnableSsl = true;
client.UseDefaultCredentials = false;
client.Credentials = basicCredential1;   
try
{
client.Send(message);
}
catch (Exception ex)
{
throw ex;
}