Q:

Cannot modify header information - headers already sent by Php ERROR

Error Is showing in the Header(location......). the error is in the same line where header('location:companies.php?rates=1'); is written    
"DestinationState"  => $_SESSION['order'][$counter]['t_stateID'],
    "DestinationZipcode"=> $_SESSION['order'][$counter]['t_zipcode'],
    "Details"           => array('DetailItem' => array( 'Weight' => $_SESSION['order'][$counter]['weight'],'Class' => '55')),
    "Accessorials"      => array('AccessorialItem' => array('Code' => 'LiftgateService')),
    "CODAmount"         => "100",
);

//print('<pre>');print_r($params);die;
   $return = $client->Create(array('request'=>$params));
  // $return = $client->Create($params);
   //$return  = $client->__call('Create', $params);
   //print('<pre>');print_r($return);die;
   $counter=0;
   $_SESSION['Saia'][$counter]['Amount']  = $return->CreateResult->RateDetails->RateDetailItem->Amount;

}
}
}   

header('location:companies.php?rates=1');
?>

A:

Add this to your first line:
<?php ob_start();?>

