Измените

 

Warning: imagepng(/var/www/mojaopstina.rs/www-root/public/images/captcha/07ae4d7e025c2b457383df6efcf16f48.png): failed to open stream: Permission denied in /var/www/mojaopstina.rs/www-root/library/Zend/Captcha/Image.php on line 563