Битрикс: почему не работает корзина?

<?
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/prolog_before.php");
if (CModule::IncludeModule("catalog")){
foreach($_GET as $KEY=>$VAL){
	$_GET[$KEY] = htmlspecialcharsEx($VAL);
}
Add2BasketByProductID($_GET["id"]);
}
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/epilog_after.php");?>

AddEventHandler("sale", "OnBeforeBasketAdd", "OnBeforeBasketAddHandler");
function OnBeforeBasketAddHandler(&$arFields)
{
  $arFields['LID']=SITE_ID;
}