مشکل در اتصال به sql server

[alirayaneh]

با سلام
کذ های من اینه


<?php
$con=mssql_connect('localhost','sa','');
if(isset($con))
{
echo "conected";
$db=mssql_select_db(ali,$con);
if(isset($db)){

mssql_select_db(ali,$con);
$tb= mssql_query("select *from admin ");
$stb=mssql_fetch_array($tb);
if(isset($stb)){
echo $stb['name'];
mssql_query("insert into admin(name) VALUES ('salam')");
}
}
}
?>


پیغام خطاش هم اینه

Warning: mssql_connect() [function.mssql-connect (http://localhost/function.mssql-connect)]: message: Login failed for user 'sa'. The user is not associated with a trusted SQL Server connection. (severity 14) in C:\server2\xampp\htdocs\a.php on line 2

Warning: mssql_connect() [function.mssql-connect (http://localhost/function.mssql-connect)]: Unable to connect to server: localhost in C:\server2\xampp\htdocs\a.php on line 2
conected
Warning: mssql_select_db() expects parameter 2 to be resource, boolean given in C:\server2\xampp\htdocs\a.php on line 6



sql server 2005
XAMPP 1.7.2
windows 7