title: 500 internal error
body: <p>I have 2 php-files at my server.
  Second's name is <code>secret.php</code>, first one is <code>index.php</code>.</p>
  
  <p>In index file I have a form which looks like:</p>
  
  <pre><code>&lt;form action="secret.php" method="post"&gt;
     &lt;!-- ... --&gt;
     &lt;input type="submit" value="Go" /&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>Everything worked before, but when I added a few changes into form code (added another input elements, etc) I got an error: 500.</p>
  
  <p>I looked with FireBug and got such picture:</p>
  
  <pre><code>POST http://server.com/secret.php 500 Internal Server Error
  </code></pre>
  
  <p>Post params are right.</p>
  
  <p>I also can't direct access of that file. Any ideas? I remember one time again: it worked well until I've added some code into form.</p>
  
  <p>File permissions are right too.</p>