ORDER es palabra reservada, para order by ...
La misma solución de antes...
Código PHP:
$insert = "SELECT * FROM xORDERS WHERE `ORDER`='$order64'";
$result = mysql_query($insert);
if (mysql_num_rows($result) == 0) {
$insert = "INSERT INTO xORDERS (`ORDER`, `HOSTING_PRICE`, `DOMAIN_PRICE`, `SUBTOTAL`, `TAX`, `TOTAL`, `DOMAIN`, `HOSTING`, `ACTIVATE`, `EXPIRATION`, `NAME`, `CLIENT`, `STATUS`) VALUES ('$order64','$HostDecim','$PriceTLD','$SubTotal','$SubTotalTAXMX','$GrandTotal','$domain64','$hosting64','$date2','$DeadLine','$nameorder','$username','PROCESANDO')";
mysql_query($insert);
}