title: Opencart fopen(/upload/system/logs/): failed to open stream: Is a directory
body: <p>I got this error in my opencart shop right after uninstalling an extension. The complete shop does not work anymore. It has not my own template and all php functions do not work. This error shows up:</p>
  
  <pre><code>Warning: fopen(/my_path/system/logs/): failed to open stream: Is a directory in /my_path/system/library/log.php on line 6
  </code></pre>
  
  <p>This is the Log class:</p>
  
  <pre><code>class Log {
      private $handle;
  
      public function __construct($filename) {
          //this is line 6
          $this-&gt;handle = fopen(DIR_LOGS . $filename, 'a');
      }
  
      public function write($message) {
          fwrite($this-&gt;handle, date('Y-m-d G:i:s') . ' - ' . print_r($message, true) . "\n");
      }
  
      public function __destruct() {
          fclose($this-&gt;handle);
      }
  }
  </code></pre>
  
  <p>Looks like the $filename var is empty. This also reflects the not working php i mentioned above. The logs directory is 755 and i tried it with 777. </p>
  
  <p>And a second error shows at the bottom of my shop:</p>
  
  <pre><code>Fatal error: Call to a member function get() on a non-object in /homepages/6/d421894284/htdocs/opencart/upload/index.php on line 104
  </code></pre>
  
  <p>Have anyone experienced this error in Opencart 2.0.1.1? Google says, that this must be a common error, but I can´t find a solution.</p>