[CI2.1.4] This page isn’t working website is currently unable to handle this request.

@cndunga What is on line 34 of your config.php? That is where the error is reported.

34 - $ark_root .= str_replace(basename($_SERVER['SCRIPT_NAME']),"",$_SERVER['SCRIPT_NAME']);

Either (a) $ark_root is not initialized before ".=" or
(b) basename(...) is conflicted because it has 2 args according to the PHP docs, not 3 like you have used.