Doesn't call user information to include "wp-load.php" in an external php file.

<?php require_once( dirname( dirname( __ FILE __ ) ) . '/wp-load.php' );

global $wpdb, $user_ID;

echo $user_ID; // reruns 0, always

is_user_logged_in() // returns false, always ?>

But I can check another one function will work. e.g. get_bloginfo('name') it will working.

Note: I can try to require_once( dirname( dirname( __ FILE __ ) ) . '/wp-config.php' ); but results is same!

What could be the reason for this? Where am I making a mistake?