for (i = 1; i < 1000; i++) { client = new SmtpClient(); client.Host = MailServer; client.Timeout = 50000; from = new MailAddress(MailSender); to = new MailAddress(MailRecipient); message = new MailMessage(from, to); StringBuilder messagetext = new StringBuilder(); messagetext.AppendFormat("This is message # {0}", i); message = new MailMessage(from, to); message.Subject = "Testing bulk email"; message.Body = messagetext.ToString(); client.Send(message); }