title: PHP Swift mailer: Failed to authenticate on SMTP using 2 possible authenticators
body: <p>When I send an email with the PHP Swift mailer to this server: smtp.exchange.example.com like this:</p>
  
  <pre><code>// Load transport
  $this-&gt;transport =
      Swift_SmtpTransport::newInstance(
         self::$config-&gt;hostname,
         self::$config-&gt;port
      )
      -&gt;setUsername(self::$config-&gt;username)
      -&gt;setPassword(self::$config-&gt;password)
      ;
  
  // Load mailer
  $this-&gt;mailer = Swift_Mailer::newInstance($this-&gt;transport);
  
  // Initialize message
  $this-&gt;message = Swift_Message::newInstance();
  
  // From
  $this-&gt;message-&gt;setFrom(self::$config-&gt;from);
  
  // Set message etc. ...
  
  // Send
  $this-&gt;mailer-&gt;send($this-&gt;message);
  </code></pre>
  
  <p>I get a strange error back:</p>
  
  <blockquote>
    <p>Failed to authenticate on SMTP server with username "user@example.com" using 2 possible authenticators</p>
  </blockquote>
  
  <p>I know for sure that the login-info is correct.</p>