title: Get SMTP server via Email Domain
body: <p>ive got an email address lets say: xxx@hotmail.com
  now i wanna get the smtp server where i can check the validation of this email address.
  for checking the email address i need to connect to the smtp server so i can send an request and get the response.
  ive got a lot of emailaddresses so its not possible to google every single dns server and add it to a list ... </p>
  
  <p>Thats how i will check if the validation is correct:</p>
  
  <pre><code>startJob.Connect("THE SMTP SERVER IP I NEED", 25);
  startJob.Authenticate("xx.xxx");
  startJob.MailFrom(String.Format("ss.sss{0}@hotmail.com", this._emailExtension));
  var response = startJob.RcptTo(item.EmailAddress);
  startJob.Quit();
  </code></pre>
  
  <p>can someone help me maybe ? would be awesome
  best regards,</p>