電子メールは多数の人に送信されません

Question

抽出がアップロードされると、およそ60人のユーザーに電子メールアラートを送信するための次のコードがあります。私はそれをローカルに実行している場合、それはすべてのアカウントに送信されますが、私はサーバーにそれをアップロードするとき、それは一人に唯一の場合を除き、すべての電子メールを送信しません。私はホスティングやサーバーのものに多くの経験を持っていないので、あなたが私に与えることができるどんな助けも素晴らしいだろう。

   if (Session["ExtractNo"].ToString() == "Extract 1") 
      { 

       //Connection String (SendEmail) 
       string SendEmail = ConfigurationManager.ConnectionStrings["Sendmail"].ConnectionString; 

       SqlDataReader reader; 
       String SendMessage = "SELECT Name, Position, Email FROM AuthorisedStaff Where Position = 'CM' or Position = 'DHOD' or Position = 'HOD'"; //<---- change position before launch 

       using (SqlConnection myConnection = new SqlConnection(SendEmail)) 
       { 
        myConnection.Open(); 
        SqlCommand myCommand = new SqlCommand(SendMessage, myConnection); 

        ArrayList emailArray = new ArrayList(); 
        reader = myCommand.ExecuteReader(); 

        var emails = new List<EmailCode>(); 

        while (reader.Read()) 
        { 
         emails.Add(new EmailCode 
         { 
          Email = Convert.ToString(reader["Email"]), 
          Name = Convert.ToString(reader["Name"]), 
          Position = Convert.ToString(reader["Position"]) 
         }); 
        } 

        foreach (EmailCode email in emails) 
        { 
         //Email Config 

         const string username = "roll@test.ac.uk"; //account address 
         const string password = "######"; //account password 

         SmtpClient smtpclient = new SmtpClient(); 
         MailMessage mail = new MailMessage(); 
         MailAddress fromaddress = new MailAddress("roll@test.ac.uk", "PTLP"); //address and from name 

         smtpclient.Host = "omavex011"; //host name for particular email address 
         smtpclient.Port = 25; //port number for particular email address 

         mail.From = fromaddress; 
         mail.To.Add(email.Email); 
         mail.Subject = ("PTLP Check"); 

         mail.IsBodyHtml = true; 

         //change context of message below as appropriate 
         mail.Body = HttpUtility.HtmlEncode(email.Name) + " <br /> <p>Part Time Payroll details are now available for checking.</p> "; 

         //smtpclient.EnableSsl = true; 
         smtpclient.DeliveryMethod = SmtpDeliveryMethod.Network; 
         smtpclient.Credentials = new System.Net.NetworkCredential(username, password); 

         smtpclient.Send(mail); 

        } 
       } 

      } 

Answer 1

これはあなたが単一SmtpClientのインスタンスを使用する方法である私のコメントで述べたように：

 if (Session["ExtractNo"].ToString() == "Extract 1") 
     { 
      //Email Config 
      const string username = "roll@test.ac.uk"; //account address 
      const string password = "######"; //account password 

      SmtpClient smtpclient = new SmtpClient(); 
      smtpclient.Host = "omavex011"; 
      smtpclient.Port = 25; 
      smtpclient.DeliveryMethod = SmtpDeliveryMethod.Network; 
      smtpclient.Credentials = new System.Net.NetworkCredential(username, password); 

      string SendEmail = ConfigurationManager.ConnectionStrings["Sendmail"].ConnectionString; 

      SqlDataReader reader; 
      String SendMessage = "SELECT Name, Position, Email FROM AuthorisedStaff Where Position = 'CM' or Position = 'DHOD' or Position = 'HOD'"; //<---- change position before launch 

      using (SqlConnection myConnection = new SqlConnection(SendEmail)) 
      { 
       myConnection.Open(); 
       SqlCommand myCommand = new SqlCommand(SendMessage, myConnection); 

       ArrayList emailArray = new ArrayList(); 
       reader = myCommand.ExecuteReader(); 

       var emails = new List<EmailCode>(); 

       while (reader.Read()) 
       { 
        emails.Add(new EmailCode { Email = Convert.ToString(reader["Email"]), 
              Name = Convert.ToString(reader["Name"]), 
              Position = Convert.ToString(reader["Position"]) 
              }); 
              } 

       foreach (EmailCode email in emails) 
       { 

        MailMessage mail = new MailMessage(); 
        MailAddress fromaddress = new MailAddress("roll@test.ac.uk", "PTLP"); //address and from name 

        mail.From = fromaddress; 
        mail.To.Add(email.Email); 
        mail.Subject = ("PTLP Check"); 
        mail.IsBodyHtml = true; 
        mail.Body = HttpUtility.HtmlEncode(email.Name) + " <br /> <p>Part Time Payroll details are now available for checking.</p> "; 
        smtpclient.Send(mail); 
       } 
      } 
      smtpclient.Dispose(); 
      }