title: Sending Outlook meeting requests without accept/decline option
body: <p>I am sending an Outlook meeting request with my .NET-program using the following as a source:
  <a href="https://stackoverflow.com/questions/461889/sending-outlook-meeting-requests-without-outlook">Sending Outlook meeting requests without Outlook?</a>
  This worked well for me, but I still have one problem/question.</p>
  
  <p>If I send an invitation directly with Outlook I have the possibility to define that I DONT want an answer (accept, decline, ..) from the invited people. So if the invited people open my mail they dont see accept, decline... buttons.</p>
  
  <p>I want this behavior also if I send auto-generated mails with my .NET-program. Is there an option to deactive the answer-feature programmatically? So that receivers DONT see accept, decline... buttons if they open my auto-generated mails?</p>
  
  <p>I already tried to set RSVP = False, DISALLOW-COUNTER = True:</p>
  
  <pre><code>BEGIN:VEVENT
  ATTENDEE;CN=receiver@mail.de;RSVP=FALSE:receiver@mail.de
  SET X-MICROSOFT-DISALLOW-COUNTER:TRUE
  .
  .
  .
  END:VEVENT
  </code></pre>
  
  <p>I saved two ICS-Files with Outlook - one with answer enabled and one with answer disabled. The above two lines were the only different ones, but it doesn't work in my generated message. If I open the mail it still shows the accept, decline, ... buttons. Any idea?</p>