title: Email Error: missing or malformed local part
body: <p>I am noticing that I get an email from my server each time an order is placed.  It looks like the customer confirmation emails are not sending.</p>
  
  <p>This is part of the error message:</p>
  
  <pre><code>A message that you sent contained one or more recipient addresses that were
  incorrectly constructed:
  
  =?utf-8?B?R3Vlc3Q=?= &lt;&gt;: missing or malformed local part
  
  This address has been ignored. The other addresses in the message were
  syntactically valid and have been passed on for an attempt at delivery.
  
  ------ This is a copy of your message, including all the headers. ------
  
  To: =?utf-8?B?R3Vlc3Q=?= &lt;&gt;
  Subject: =?utf-8?B?SW50ZWxsaWdlbnQgV29ya3Nob3A6IE5ldyBPcmRlciAjIDEwMDAwMDAzMA==?=
  </code></pre>
  
  <p>It looks like it’s only when the user checks out without registering </p>