Linux, Apache, MySQL, PHP

Hi,

I have a two mirror sites,
http://shop.XXXXX.us and http://shop1.XXXXX.us
I am trying to use the SOAP V2 in both the sites. Its working fine in ‘http://shop.XXXXX.us’
But in ‘http://shop1.XXXXX.us’, it is throwing a SOAP-ERROR: Parsing WSDL: saying failed to load external entity
When I open the SOAP URL ‘http://shop1.XXXXX.us/index.php/api/v2_soap/?wsdl=1’ in browser, XML file is loaded properly.
Not able to get what the exact error is. Pls help if possible.

$inactive = 100;
    
$session_life = time() - $_SESSION['timeout'];
    
if ($session_life > $inactive)
{ exit(header("Location: out")); }
    
$_SESSION['timeout'] = time();

<?php  if ((bool)$_SESSION["blended_learning_is_administrator"] = true) { ?>
<tr><td><button id="btnManageUsers" type="button" style="width: 100%;">Manage Users</button></td></tr>
<tr><td><button id="btnNewUser" type="button" style="width: 100%;">New User</button></td></tr>
<?php } ?>

while ($mysql_row = $mysql_query->fetch())
{
    $_SESSION["blended_learning_user_name"] = $mysql_row["user_name"];
    $_SESSION["blended_learning_is_administrator"] = $mysql_row["is_administrator"];

    exit(header("Location: " . $_SESSION["blended_learning_domain_name"] . "mypage"));
}