Testing for correct email addy/password TSql

I am making a login form on my site, and need a little bit of help. I keep receiving an error when I use this script:

<?php

$em = $_REQUEST["email"];
$pa = md5($_REQUEST["password"]);

//connectioninfo hidden   

$connectionInfo = array( "UID"=>$uid,                              
                         "PWD"=>$pwd,                              
                         "Database"=>$databaseName);
$conn = sqlsrv_connect( $serverName, $connectionInfo);

$tsql = "SELECT email, password FROM users WHERE email = $em AND password = $pa";

$stmt = sqlsrv_query( $conn, $tsql);    

if($stmt)
{
    $ot =
    "Hi, " . $em;
}
else
{
  $ot =
  "<p>Oh, no! My Account is currently unavailable right now, please try again later.</p>";
}

?>

The error I keep getting is:

Oh, no! My Account is currently unavailable right now, please try again later.

Can someone please hel me understand why it is not displaying the Hi, $em message when I login ,and how I may go about fixing it.

Also, just to get this out of the way, yes, I am using the correct login details. :)

Thanks jase

You have several issues:

1. You're using REQUEST instead of POST. You really should use POST.
2. Your code is vulnerable to SQL injection: http://php.net/manual/en/security.database.sql-injection.php
3. You have no quotes around your string literals, which is likely causing your problem.