My Exchange server is connected to my ISP with a 256K pipe.My Exchange server is the “ultimate” destination (receiver-smtp)and my ISP acts as a intermediate destination (sender-smtp).Lets say I have mail restrictions setup on my exchange server and filtering by 3rd party software that filter’s attachements,.jpg ect.When mail is sent to my exchange server is the “whole” mail (Data included)sent down my 256K pipe and then rejected based on restictions and filtering at my exchange server? Or, is the ip info about the message(Size,Intended recipient, originating sender)sent up and down the pipe and based on this info rejected? Now, what I would like to determine is, is my 256K connection to my ISP being consumed by mail that is rejected by my exchange+3rd party software or is the (data) never entering my 256k line, and actually stopped at the “intermediate” destination based on the Ip header info? I hope this all makes sense???