Измените

 

Warning: imagepng(/var/www/mojaopstina.rs/www-root/public/images/captcha/1c5ed67d1fe97106b3d9735a73e4f849.png): failed to open stream: Permission denied in /var/www/mojaopstina.rs/www-root/library/Zend/Captcha/Image.php on line 563