title: Debugging 500 Internal Server Error on PHP running on IIS7 cluster
body: <p>Recently my ISP switched our website to an IIS7.0 high availibility cluster. The website is running on PHP5.2.1 and I can only upload files (so no registry tweaks). I had tested the website before and everything seemed to be working, but now the checkout page fails with:</p>
  
  <blockquote>
  500 - Internal server error.
  There is a problem with the resource you are looking for, and it cannot be displayed. 
  </blockquote>
  
  <p>As error messages go, this isn't very informative. I've tried: </p>
  
  <pre><code>ini_set('display_errors', 1);
  ini_set('error_log', $file_php_can_write_to );
  </code></pre>
  
  <p>but both don't seem to do anything.</p>
  
  <p>Anyone know how to get better debugging output?</p>