c# - 无法在服务器上发送邮件。获取异常 SMTP 服务器需要安全连接或客户端未通过身份验证

Question

伙计们，我有一个类(class)，我要向数据库中的所有学生发送邮件。当我在本地主机上发送邮件时，邮件很容易发送，但是当我将代码上传到服务器时。我收到此异常:

System.Net.Mail.SmtpException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at at System.Net.Mail.MailCommand.CheckResponse(SmtpStatusCode statusCode, String response) at System.Net.Mail.MailCommand.Send(SmtpConnection conn, Byte[] command, MailAddress from, Boolean allowUnicode) at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, Boolean allowUnicode, SmtpFailedRecipientException& exception) at System.Net.Mail.SmtpClient.Send(MailMessage message) at HotelWeb.SMTPHelper.SendEmail(String From, String FromDisplayName, String To, String Cc, String Bcc, String Subject, String Body, Boolean SendMailInBackGround) in e:\hostingspaces\ubi9009\ihmsgr.taqwatechnologies.net\wwwroot\App_Code\SMTPHelper.cs:line 140 at HotelWeb.MAILnSMS.sendBulkMail() in e:\

hostingspaces\ubi9009\ihmsgr.taqwatechnologies.net\wwwroot\App_Code\MAILnSMS.cs:第 95 行

我的代码在本地机器上运行良好，但在服务器上无法正常运行是这样的:

public static void sendBulkMail() {

        _ds = new DataSet();



        SMTPBAL smtpbl = new SMTPBAL(0);
        smtpbl.LoadAll(_ds);

        string server = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["SMTPX"].ToString();
        int smtpPort = WebHelper.Cast(_ds.Tables[smtpbl.SqlEntityX].Rows[0]["smtpPort"].ToString(), 0);
        string From = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Email"].ToString();
        string User = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["User"].ToString();
        string Password = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Password"].ToString();
        string sDisclaimer = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Disclaimer"].ToString();
        bool EnableSSl = WebHelper.Cast(_ds.Tables[smtpbl.SqlEntityX].Rows[0]["EnableSll"], false);
        string EmailAddress = string.Empty;

        StudentBAL _stbl = new StudentBAL(0);
        _stbl.LoadAll(_ds);

        foreach (DataRow dr in _ds.Tables[_stbl.SqlEntityX].Rows)
        {
            try
            {
                if (dr["Email"] != DBNull.Value)
                {
                    if (IsValidMailAddress(dr["Email"].ToString()))
                    {
                        string Message = "Dear parent,<br/><br/> <br/> The Attendance for current course/semester of your ward," + dr["Name"].ToString() + " is available on the given below link.Please check and contact HOD in case any enquiry.<br/><br/><br/>Copy below link to your browsers address bar. <br/><br/>http://ihmsgr.taqwatechnologies.net/login/login.aspx <br/>User Name :" + dr["LoginEmailAddress"].ToString() + " / " + dr["EmailAddress"].ToString() + "<br/>Password : " + dr["Password"].ToString() + "<br/><br/><br/>Regard's<br/><br/>Institute of hotel management.<br/>Srinagar.";


                        SMTPHelper SMTP1 = new SMTPHelper(server, smtpPort, From, Password, EnableSSl, true);
                        SMTP1.IsHTML = true;

                        SMTP1.SendEmail(From, "Institute of hotel management", dr["Email"].ToString(), "", "", "Attendance status of your ward.", Message, false);
                    }
                }
            }
            catch (Exception err) {


            }

        }

    }

我正在使用服务器上的托管空间 http://www.arvixe.com/请帮忙

Answer 1

该错误消息通常是由以下原因之一引起的:

• 不正确的连接设置，例如指定的错误端口 安全或非安全连接
• 凭据不正确。请验证用户名和密码 组合，以确保凭据正确无误。

另外，如果还是不行，尝试将SmtpClient的DeliveryMethod设置为SmtpDeliveryMethod.Network

以下是相同的代码片段

var smtp = new SmtpClient
           {
               Host = "smtp.gmail.com",
               Port = 587,
               EnableSsl = true,
               DeliveryMethod = SmtpDeliveryMethod.Network,
               UseDefaultCredentials = false,
               Credentials = new NetworkCredential(fromAddress.Address, fromPassword)
           };