无法从 windows 2008R2 上托管在 IIS 运行 上的 asp.net（框架版本 4）应用程序发送邮件？

Question

我的应用程序托管在 IIS 运行 上 windows 2008R2.Code 发送邮件如下所述。

public bool SendMail(string to, string cc, string subject, string body)
    {
        bool abc = false;
        System.Net.Mail.SmtpClient smtpClient = null; 
        System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
        bool IsSSLfailed = false;
        bool allPortsFailed = false;
        bool SSLEnabled = false;
        bool CertificateByPassed = false;
        smtpClient = new System.Net.Mail.SmtpClient();
    again: try
        {

            //  SmtpClient smtpserver = new SmtpClient("smtp.gmail.com", 25);

            string from = ConfigurationSettings.AppSettings.Get("UserName");
            string Password = ConfigurationSettings.AppSettings.Get("Password");
            message.From = new MailAddress(from);
            message.To.Add(to);
            message.Subject = subject;
            message.IsBodyHtml = true;
            message.Body = body;
            message.Subject = WebUtility.HtmlEncode(subject);
            message.SubjectEncoding = Encoding.UTF8;
            message.IsBodyHtml = true;
            message.Body = WebUtility.HtmlDecode(body);
            message.BodyEncoding = Encoding.UTF8;



            smtpClient.Timeout = 10000;
            message.SubjectEncoding = Encoding.UTF8;
            if (IsSSLfailed)
            {
                if (smtpClient.Port == 587)
                {
                    smtpClient.Port = 465;
                }
                else if (smtpClient.Port == 465)
                {
                    smtpClient.Port = 25;
                }
                else if (smtpClient.Port == 25)
                {
                    smtpClient.Port = 2525;
                    allPortsFailed = true;
                }


            }
            else
            {
                smtpClient.Port = 587;
            }
            smtpClient.EnableSsl = SSLEnabled;
            if (!CertificateByPassed)
            {
                BypassCertificateError();    
            }

            System.Net.NetworkCredential nc = new System.Net.NetworkCredential(from, Password);
            smtpClient.Credentials = nc;
            smtpClient.Send(message);
            abc = true;
        }
        catch (System.Net.Mail.SmtpFailedRecipientException ex)
        {
            IsSSLfailed = true;
            logger.ErrorFormat("Error occured in SendMail() method,CertificateBypassed:" + CertificateByPassed.ToString() + "  SSLEnabled: " + SSLEnabled.ToString() + " smtp User:" + ((NetworkCredential)smtpClient.Credentials).UserName + " pwd:" + ((NetworkCredential)smtpClient.Credentials).Password + " smtpClient.DeliveryMethod:" + smtpClient.DeliveryMethod.ToString() + " smtpClient.EnableSsl:" + smtpClient.EnableSsl.ToString() + " smtpClient.Host:" + smtpClient.Host.ToString() + " smtpClient.Port:" + smtpClient.Port.ToString()+ " smtpClient.UseDefaultCredentials:" + smtpClient.UseDefaultCredentials.ToString() + " Detailed error:{0}{1}", Environment.NewLine, ex.Message.ToString());
            logger.ErrorFormat("Inner Exception", Environment.NewLine, ex.InnerException != null ? ex.InnerException.Message.ToString() : string.Empty);

            if (!allPortsFailed)
            {
                goto again;
            }
            else if (!SSLEnabled)
            {
                SSLEnabled = true;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;
            }
            else if (!CertificateByPassed)
            {
                CertificateByPassed = true;
                SSLEnabled = false;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;

            }
            this.upForm.Update();
            throw ex;
        }
        catch (System.Net.Mail.SmtpException ex)
        {
            IsSSLfailed = true;
            logger.ErrorFormat("SendMail SmtpException,CertificateBypassed:" + CertificateByPassed.ToString() + "  SSLEnabled: " + SSLEnabled.ToString() + " smtp User:" + ((NetworkCredential)smtpClient.Credentials).UserName + " pwd:" + ((NetworkCredential)smtpClient.Credentials).Password + " smtpClient.DeliveryMethod:" + smtpClient.DeliveryMethod.ToString() + " smtpClient.EnableSsl:" + smtpClient.EnableSsl.ToString() + " smtpClient.Host:" + smtpClient.Host.ToString() + " smtpClient.Port:" + smtpClient.Port.ToString() + " smtpClient.UseDefaultCredentials:" + smtpClient.UseDefaultCredentials.ToString() + "  StatusCode:" + ex.StatusCode.ToString() + " " + smtpClient.Port.ToString(), Environment.NewLine, ex.Message.ToString());
            logger.ErrorFormat("SendMail Inner ExceptionSmtpException StatusCode:" + ex.StatusCode.ToString() + " " + smtpClient.Port.ToString(), Environment.NewLine, ex.InnerException != null ? ex.InnerException.Message.ToString() : string.Empty);

            if (!allPortsFailed)
            {
                goto again;
            }
            else if (!SSLEnabled)
            {
                SSLEnabled = true;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;
            }
            else if (!CertificateByPassed)
            {
                CertificateByPassed = true;
                SSLEnabled = false;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;

            }
            this.upForm.Update();
            throw ex;
        }
        catch (Exception ex)
        {
            IsSSLfailed = true;
            logger.ErrorFormat("SendMail error sending mail,CertificateBypassed:" + CertificateByPassed.ToString() + "  SSLEnabled: " + SSLEnabled.ToString() + " smtp User:" + ((NetworkCredential)smtpClient.Credentials).UserName + " pwd:" + ((NetworkCredential)smtpClient.Credentials).Password + " smtpClient.DeliveryMethod:" + smtpClient.DeliveryMethod.ToString() + " smtpClient.EnableSsl:" + smtpClient.EnableSsl.ToString() + " smtpClient.Host:" + smtpClient.Host.ToString() + " smtpClient.Port:" + smtpClient.Port.ToString() +" smtpClient.UseDefaultCredentials:" + smtpClient.UseDefaultCredentials.ToString() + " " + " " + smtpClient.Port.ToString(), Environment.NewLine, ex.Message.ToString());
            logger.ErrorFormat("SendMail error sending mail,CertificateBypassed:" + CertificateByPassed.ToString() + "  SSLEnabled: " + SSLEnabled.ToString() + " smtp User:" + ((NetworkCredential)smtpClient.Credentials).UserName + " pwd:" + ((NetworkCredential)smtpClient.Credentials).Password + " smtpClient.DeliveryMethod:" + smtpClient.DeliveryMethod.ToString() + " smtpClient.EnableSsl:" + smtpClient.EnableSsl.ToString() + " smtpClient.Host:" + smtpClient.Host.ToString() + " smtpClient.Port:" + smtpClient.Port.ToString() + " smtpClient.UseDefaultCredentials:" + smtpClient.UseDefaultCredentials.ToString() + " " + " " + smtpClient.Port.ToString(), Environment.NewLine, ex.InnerException != null ? ex.InnerException.Message.ToString() : string.Empty);

            if (!allPortsFailed)
            {
                goto again;
            }
            else if (!SSLEnabled)
            {
                SSLEnabled = true;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;
            }
            else if (!CertificateByPassed)
            {
                CertificateByPassed = true;
                SSLEnabled = false;
                IsSSLfailed = false;
                allPortsFailed = false;
                goto again;

            }
            this.upForm.Update();
            throw ex;
        }

        return abc;

    }
    public static void BypassCertificateError()
    {
        try
        {
            ServicePointManager.ServerCertificateValidationCallback +=

                    delegate(
                        Object sender1,
                        X509Certificate certificate,
                        X509Chain chain,
                        SslPolicyErrors sslPolicyErrors)
                    {
                        return true;
                    };
        }
        catch (Exception ex)
        {

            throw ex;
        }
    }

正如您从代码中看到的，我已经检查了所有用于发送邮件的端口。 此相同代码适用于 windows 7/8 上托管的应用程序，但不适用于 windows 2008R2。 以下是我收到的错误消息

SendMail SmtpException,CertificateBypassed:False SSLEnabled: False smtpClient.DeliveryMethod:Network smtpClient.EnableSsl:False smtpClient.Host:SMTP.GMAIL.COM smtpClient.Port:587 smtpClient.UseDefaultCredentials:False StatusCode:GeneralFailure

innerexception.This 中没有任何内容重复所有 ports.I 我通过 gmail.I 发送此邮件已在具有相同 gmail 帐户的服务器上使用 MS Outlook 进行了测试，它是工作正常，所以我猜防火墙限制不适用于我的 case.I 我还在 gmail 设置中启用了 "Access for less secure app"。

Answer 1

McAfee 正在阻止邮件 attemps.Never 对此表示怀疑，因为我可以从 outlook 发送邮件，但无法从我的 code.Just 发送邮件，包括 w3wp.exe 以排除在群发邮件中