Error 1: PHP Fatal error: Uncaught exception ‘RuntimeException’ with message ‘Library path DIR cannot be found.’ in /home/yourdomain/public_html/libraries/loader.php:251 Stack trace:
The problem is your server’s php is low, you must upgrade php versions to 5.4. See the Technical requirements for Joomla 3.x from here: http://docs.joomla.org/Technical_requirements