[PHP-WIN] mysql_fetch_array warnings.

[Martin.Andrew]

testing locally I use the following code

        $query = "select * from users where UserName LIKE '$username'";
        $result = mysql_query($query);
                if ($row = mysql_fetch_array($result)) {
                ...
                ...
                }

works fine.

On the ISP machine I get the following warnings?

Supplied argument is not a valid MySQL result resource !!

Do I need to change a setting?