PHPBB filestats

[guest]

i got this script that showing an error

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/nortesav/public_html/forum_test.php on line 30
User stats
we have 9 registered users
The last user was xLIL MOU$EY4
Your stats

<?
include('includes/function.php');
db_connect('forum');

$cookie = $_COOKIE['noresavage_forum_data'];
if(!isset($cookie)){
 $logedm = "Not logged in!";
}else{

$id = clean($cookie);
$id = explode('\"userid\"',$id);
$id = $id[1];
$id = explode(';i:', $id);
$id = $id[1];
$id = explode(';}', $id);
$id = $id[0];

$query = mysql_query("select * from phpbb_users where user_id='$id'");
while($x = mysql_fetch_array($query)){
 $user['name'] = $x['username'];
 $user['id'] = $x['user_id'];
 $user['npm'] = $x['user_unread_privmsg'];
 $logedm = "Welcome, ".$user['name']."<br>You have ".$user['npm']." unread PMs.<br>";
}
}
$users = mysql_query("select user_id from phpbb_users");
$users = mysql_num_rows($users);
$users = $users - 1;
$l_user = mysql_query("select * from phpbb_users order by user_id DESC limit 1");
while($l = mysql_fetch_array($l_user)){
 $l_user = $l['username'];
}
$ustat = "we have ".$users." registered users<br>The last user was ".$l_user;
mysql_close();

echo "<b>User stats</b><br>";
echo $ustat;
echo "<br><b>Your stats</b><br>";
echo $logedm;
?>

how could i fix it?

[bradgrafelman]

Change this:

$query = mysql_query("select * from phpbb_users where user_id='$id'"); 

to this:

$query = mysql_query("select * from phpbb_users where user_id='$id'") or die('Mysql error: ' . mysql_error() . '<br><br>Query was: ' . "select * from phpbb_users where user_id='$id'"); 

and paste us the output.