DOESN'T FUCKING WORK

<?PHP
session_start(); //open the session for session variables
include 'processerrors.php';
logstats();
set_error_handler("logmyerror");
$host = "localhost"; //the host address to connect to
$user = "root"; //the database user that we connect using
$pass = "09k6CcsGxBq7p"; //the database user's password
$db = "LogIn"; //the database to access

//use the variables declared above to connect to the database
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");
//select the specific database to read from
mysql_select_db($db) or die ("Unable to connect to database...");
// The query
// Find the location in the table of the entered username
$getUser = "SELECT `Password` FROM `users` WHERE `Username`='" . $_POST["txtUsername"] . "'";


//run the query
$result = mysql_query($getUser) or die ("Error in query: $query.".mysql_error());

if(mysql_num_rows($result) == 1) {
    $pwd = mysql_fetch_row($result);
    if($_POST["txtOldPassword"] == $pwd[0]) {
        $updatePass = "UPDATE `users` SET `password`='".$_POST["txtPassword"]."' WHERE `Username`='".$_POST["txtUsername"]."'";
        $newresult = mysql_query($updatePass);
        echo "Success!";
    } else {
        echo "Failed, we found a user with that name, but the password appears to be incorrect.";
    }
} else {
    echo "Failed, we couldn't find a username with that name.";
}

mysql_free_result($result); // free space in memory
mysql_close($connection); //close the connection


?>