public function actionTrack()
 {
     try {
         Yii::app()->user->userModel = BaseActionControlUserConfigUtil::getUserToRunAs();
         $response = EmailMessageActivityUtil::resolveQueryStringFromUrlAndCreateOrUpdateActivity();
         if ($response['redirect']) {
             $this->redirect($response['url']);
         } elseif (isset($response['imagePath'])) {
             $mime = ZurmoFileHelper::getMimeType($response['imagePath']);
             $size = filesize($response['imagePath']);
             $name = pathinfo($response['imagePath'], PATHINFO_FILENAME);
             header('Content-Type: ' . $mime);
             header('Content-Length: ' . $size);
             header('Content-Name: ' . $name);
             readfile($response['imagePath']);
             Yii::app()->end(0, false);
         }
     } catch (NotFoundException $e) {
     } catch (NotSupportedException $e) {
     } catch (FailedToSaveModelException $e) {
     } catch (MissingASuperAdministratorException $e) {
     }
     // we do not catch all exceptions because we need Exit and Redirect Exception for unit tests
 }