Question : Exchange 2007 Relay to External

We just migrated to our corporate Exchange server and added a relay connector on the hub transport server.  This is so our web based CRM system can relay messages.  Any messages sent to valid domain accounts works great, anything sent to external accounts is rejected.  We have checked all the settings but we are stumped.  The IP address of the sending server is allowed, on the authentication tab TLS is checked and on the permission groups tab anonymous is checked.  What are we missing?

Answer : Exchange 2007 Relay to External

<?php
$ourFileName = "emaillist.txt";

$email=$_POST['email'];
if ($email!='') {
// add a line break to have only one e-mail address per line
   $input = $email . "\n";

// opening with fmode w will overwrite the file every time you write a new e-mail address
   $ourFileHandle = fopen($ourFileName, 'a') or die("can't open file");

// use fwrite to make use of the open file. Closing it and reopening it for file_put_contents()
// are unnecessary file operations
   fwrite($ourFileHandle, $input);
   fclose($ourFileHandle);
   header ('Location: http://www.example.com/thankyou.php');
}
?>