title: Mamp Pro 4: Apache won't start
body: <p>I used Mamp Pro 4 for a while with no problem on my Mac (Os X 10.11), then, suddenly, Apache won't start. I got an error: "Check the log" but log is empty.</p>
  
  <p>I have made several test:</p>
  
  <ul>
  <li>reinstalled Mamp Pro 4 (4.0.6);</li>
  <li>rebuild permissions using utility disk and Onyx</li>
  <li>update Mac os X El Captain to Sierra;</li>
  <li>started Apache/MySql as "www" or as "user"</li>
  </ul>
  
  <p>Note:  </p>
  
  <ul>
  <li>1) starting system Apache it works</li>
  <li>2) using MAMP (not pro) Apache works fine.</li>
  </ul>
  
  <p>Any other suggestions ? Thanks </p>