IIS PHP Database มันไม่ยอมติดต่อ DB อะครับหาวิธีแก้หลายวันแล้วทําตามทุกวิธีแล้วก็แก้ไม่ได้

<?php
$dns = 'sqlsrv:Server=localhost\sqlexpress;Database=northwind;';
$dbh = new PDO($dns, '', ''); //pdo($dns, user, pass)

$query = 'SELECT EmployeeID, LastName, FirstName, Title, TitleOfCourtesy, BirthDate, Address, City, Country FROM Employees  WHERE EmployeeID = :employeeID;';
$stmt = $dbh->prepare($query);
$stmt->bindParam(':employeeID', $id, PDO::PARAM_INT);
$stmt->execute();

while ($result = $stmt->fetch(PDO::FETCH_OBJ)) {
    echo '<tr>';
    echo "<td><img src=\"images/imageicon.png\" 
        onmouseover=\"javascript:showtrail('imagedb.php?db=sqlsrv&amp;id={$result->EmployeeID}');\" 
        onmouseout=\"javascript:hidetrail();\" style=\"border-width:0px;\" /></td>";
    echo "<td>{$result->TitleOfCourtesy} {$result->LastName} {$result->FirstName}</td>";
    echo "<td>{$result->Title}</td>";
    echo "<td>" . (new DateTime($result->BirthDate))->format('d M Y') . "</td>";
    echo "<td>{$result->Address}</td>";
    echo "<td>{$result->City}</td>";
    echo "<td>{$result->Country}</td>";
    echo "</tr>\n"; 
}
?>

$serverName = 'localhost\sqlexpress';
$connectionInfo = array( 'Database'=>'northwind', 'UID'=>'', 'PWD'=>'');
$conn = sqlsrv_connect( $serverName, $connectionInfo);
if( $conn === false ) {
     die( print_r( sqlsrv_errors(), true));
}

$sql = 'SELECT EmployeeID, LastName, FirstName, Title, TitleOfCourtesy, BirthDate, Address, City, Country FROM Employees  WHERE EmployeeID = ?;';
$params = array($id);
$stmt = sqlsrv_query($conn, $sql, $id);
if( !$stmt ) {
    die( print_r( sqlsrv_errors(), true));
}

while ($result = sqlsrv_fetch_object($stmt)) {
    echo '<tr>';
    echo "<td><img src=\"images/imageicon.png\" 
        onmouseover=\"javascript:showtrail('imagedb.php?db=sqlsrv&amp;id={$result->EmployeeID}');\" 
        onmouseout=\"javascript:hidetrail();\" style=\"border-width:0px;\" /></td>";
    echo "<td>{$result->TitleOfCourtesy} {$result->LastName} {$result->FirstName}</td>";
    echo "<td>{$result->Title}</td>";
    echo "<td>" . (new DateTime($result->BirthDate))->format('d M Y') . "</td>";
    echo "<td>{$result->Address}</td>";
    echo "<td>{$result->City}</td>";
    echo "<td>{$result->Country}</td>";
    echo "</tr>\n"; 
}
?>

// รู้สึกจะไม่มี สงสัยสับสนกับของ mysqli ที่เขียนได้ 2 แบบ

<?php
$ip = $_SERVER['REMOTE_ADDR'];
$server = '';
$link = mssql_connect($server, '', '');
$selectdb = mssql_select_db("");

if (!$link)
{
	die('DB Error');
}
if (!$selectdb) 
{
	die('DB Select Error');
}
?>