title: FB doesn't return access_token for my app, no error msg specified.
body: <p>This is my first FB app, website integraton, and I can't get FB's sample php code to return an access_token.</p>
  
  <p>I have checked:
  - app setup screens on developer.facebook.com seem ok (no warnings or errors)
  - include latest github version of facebook.php on page
  - app_id and app_secret are correct</p>
  
  <p>The code below is copied from the FB docs, but <code>$response</code> doesn't return anything and <code>$user-&gt;name</code> is empty.</p>
  
  <p>Can anyone give me a hand here? Is there a debug technique that could tell me why it's failing to succeed in getting a access_token?</p>
  
  <pre><code>$token_url = "https://graph.facebook.com/oauth/access_token?"
     . "client_id=" . $app_id . "&amp;redirect_uri=" . urlencode($my_url)
     . "&amp;client_secret=" . $app_secret . "&amp;code=" . $code;
  
   $response = @file_get_contents($token_url);
  
   $params = null;
   parse_str($response, $params);
  
   $graph_url = "https://graph.facebook.com/me?access_token=" 
     . $params['access_token'];
  
   $user = json_decode(file_get_contents($graph_url));
   echo("Hello " . $user-&gt;name)."&lt;br&gt;";
  </code></pre>