Im having a problem with this, if anyone could help i would be greatful 
Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in /home/hkdropbo/public_html/Register.php on line 28
<?php
require('config.php');
if(isset($_POST['submit'])){
// perform the verification
$email1 = $_POST['email1'];
$email2 = $_POST['email2'];
$pass1 = $_POST['pass1'];
$pass2 = $_POST['pass2'];
if($email1 == $email2) {
if($pass1 == $pass2){
//all good, carry on
$name = mysql_escape_string($_POST['name']);
$lname = mysql_escape_string($_POST['lname']);
$uname = mysql_escape_string($_POST['uname']);
$email1 = mysql_escape_string($email1);
$email2 = mysql_escape_string($email2);
$pass1 = mysql_escape_string($pass1);
$pass2 = mysql_escape_string($pass2);
//////// 28.-----------
$pass1 = md5($pass1);
//kollar så ingen annan användare med samma användarnamn finns
$sql = mysql_query("SELECT * FROM `users` WHERE `uname` = '$uname'");
if(mysql_num_rows($sql) >0){
echo "Sorry, that user already exists.";
exit();
}
//////////////////28.--------------
mysql_query("INSERT INTO `users` (`id`, `name`, `lname`, `uname`, `email`, `pass`) VALUES (NULL, '$name', '$lname', '$uname', '$email1', '$pass1')");
}else{
echo "Sorry, your passwords do not match.<br>";
exit();
}
}else{
include "regform.php";
//$form = <<<EOT
//EOT;
//echo $form;
}}
?>
