/captcha/png/HG9LPF0L0BVRH96K0T1W
  (8) Trying to get property of non-object   CaptchaController.php   line 49     16-10-18   23:55
FrontController->dispatch() # line   18, file: /home/arfooo/www/index.php
  call_user_func_array(Array[2], Array[1]) # line  211, file: /home/arfooo/www/core/FrontController.php
    CaptchaController->pngAction("HG9LPF0L0BVRH96K0T1W") # line    0, file: unknown