title: Why is my bulk email being flagged as spam?
body: <p>I need to send newsletters to our customers (nearly 500,000), We are using Google Apps as our mail providers, so ultimately it is Gmail.</p>
  
  <p>I tried several ways of achieving this, but I've run into a couple of problems:</p>
  
  <ul>
  <li><p>Sometimes, it is hanging up (not sending mails after 255). So I decided to split the emails up into blocks of 255 and tried it again, but this too hangs up once in a while. I can't rely on that.</p></li>
  <li><p>Also, my clients say that my newsletters end up in their "spam" folder because Google's mail server has labeled them as spam mails.</p></li>
  </ul>
  
  <p>What can I do to fix this problem?</p>