title: Sender address rejected: Domain not found
body: <p>I'm getting the error below when sending mail via smtp through google apps mail. Can anyone see why I get this error? As far as I can tell my domain exists!</p>
  
  <pre><code>THIS IS A WARNING MESSAGE ONLY.
  
  YOU DO NOT NEED TO RESEND YOUR MESSAGE.
  
  Delivery to the following recipient has been delayed:
  
       a.kozikowski@tutek.pl
  
  Message will be retried for 2 more day(s)
  
  Technical details of temporary failure:
  Google tried to deliver your message, but it was rejected by the server for the recipient domain tutek.pl by mx.maxus.pl. [213.241.89.166].
  
  The error that the other server returned was:
  450 4.1.8 &lt;aquarius@aquariusprams.co.uk&gt;: Sender address rejected: Domain not found
  </code></pre>