Problema al conectar a MySQL

[miguel_92]

Mi página es:

<?php
// By PeChU!!
if(stristr($_SERVER['PHP_SELF'], "config.php")) die('asdada');
$host = "localhost"; // host mysql
$user = "sa"; // mysql username
$pass = "*****"; // mysql password
$db = "MiFlyff\SQLEXPRESS"; // mysql db

mysql_connect($host,$user,$pass) or die(mysql_error());
mysql_select_db($db) or die(mysql_error());

function nw($N, $C){
$reg = mysql_query("INSERT INTO accounts (username, password, accesslevel) VALUES( '$N', '$C', '100')")or die(mysql_error());
return $reg;
}
function exi($user){
$check = mysql_query("SELECT * FROM accounts WHERE username = '$user'");
$check2 = mysql_num_rows($check);
return $check2;
}

?>

Tengo el siguiente error:

Warning: mysql_connect() [function.mysql-connect]: Access denied for user 'sa'@'localhost' (using password: YES) in V:\Programas\Servidor\wamp\www\config.php on line 9
Access denied for user 'sa'@'localhost' (using password: YES)