If you want to connect with PDO, there is a bug in samples/common/config.php
to connect, you have to complete the PDO-command (what i have written in bold)
// PDO
require_once (dirname(FILE).'/connector/db_pdo.php");
$res = new PDO(“mysql:host=192.168.1.251;dbname=schedulertest”, “scheduler”, “scheduler”);
$dbtype = “PDO”;
Of course, you have to use YOUR host-name, db-name, pw etc …