title: How to suppress read receipt via IMAP?
body: <p>I want implement a confirmation dialog for sending email read receipts in my application. The application uses IMAP to communicate with the mail server, which is currently restricted to a Microsoft Exchange Server 2010.</p>
  
  <p>The receipt is obviously automatically send by the server when the <code>\Seen</code> flag is sent. So the IMAP commands would look something like this:</p>
  
  <pre><code>c1 LOGIN username password
  c2 SELECT mailbox
  c3 UID STORE 123 flags \Seen
  </code></pre>
  
  <p>(Btw. this stands in contrast to the solution found in <a href="https://stackoverflow.com/a/1293857/432681">another stackoverflow question</a>, which said that setting the <code>\Seen</code> flag would not cause the Exchange Server to send receipts.)</p>
  
  <p>Though how to handle the case when the user does <strong>not</strong> want to send a read receipt?</p>
  
  <p>My initial idea was simply not to set the <code>\Seen</code> flag. Though this causes the server to automatically send a notification to the sender that the email was deleted without being read in case the message is deleted from the server.</p>
  
  <p>Also marking the message with <code>\Deleted</code> and <code>\Seen</code> before expunging didn't help:</p>
  
  <pre><code>c1 UID STORE 123 flags (\Deleted \Seen)
  c1 UID EXPUNGE 123
  </code></pre>
  
  <p>So how to explicitly suppress the read receipt message in case the user doesn't want to send one?</p>