define("USERNAME", "XXXX@XXXXXXXX.com");
    define("PASSWORD", "XXXXXXXX");
    define("SECURITY_TOKEN", "XXXXXXXXXXXXXXXXX");
    define("SOAP_CLIENT_BASEDIR", trailingslashit( ABSPATH ) . "../soapclient");
    require_once (SOAP_CLIENT_BASEDIR.'/SforceEnterpriseClient.php');
    require_once (SOAP_CLIENT_BASEDIR.'/SforceHeaderOptions.php');
    try {
      $mySforceConnection = new SforceEnterpriseClient();
      $mySforceConnection->createConnection(SOAP_CLIENT_BASEDIR.'/enterprise.wsdl.xml');
      $mySforceConnection->login(USERNAME, PASSWORD.SECURITY_TOKEN);

      $sObject = new stdclass();
      $sObject->FirstName = $first_name;
      $sObject->LastName = $last_name;
      // INSERT SOME FIELD HERE TO ATTACH AN ARRAY OF COURSES THE USER IS ATTACHED TO

  $createResponse = $mySforceConnection->upsert("Email", array($sObject), 'Contact');

    } catch (Exception $e) {
      echo $mySforceConnection->getLastRequest();
      echo $e->faultstring;
    }