How do I prevent (or keep to a minimum) Spam on our Exchange 2003 Server while keeping our pulic IP address and domain off of "Black lists'? Both (enormous amounts of Spam and our External Exchange server is on some "Black lists" and being bounced by some email sites "AOL is the big one") are currently slowing down our business. I have already seen some of the other suggestions made by yourself and others. One is I turned on filtering and set up a “tar pit”. I apparently need more because it is only slowing SPAM down. Can you offer some additional solutions?