<div class="markdown">
<p>It’s possible that this was a side-effect of my starting with an Exchange proxy, and then switching to our internal Exchange IMAP server, but FWIW. </p>
<ol>
<li><p>Edit IMAP account settings and select Subscriptions. Turn off the Client Subscription checkbox for <code>Calendar</code> and <code>Contacts</code>. </p></li>
<li><p>Maybe I’m misinterpreting what I’m seeing, but at least on our server, the IMAP server seems to be using <code>Deleted Items</code> for trash, and the Exchange clients are using <code>Trash</code> for trash. Needless to say, that gets confusing. So I went to <code>Deleted Items</code>, double clicked, went to <code>Rules</code>, and added an <code>Action</code>. </p>
<p><code>Move to Mailbox ACCOUNTNAME > Trash</code> </p></li>
</ol>
<p>Now whenever the IMAP server puts things in <code>Deleted Items</code>, MailMate promptly moves them to the <code>Trash</code> folder instead. </p>
</div>