> I have a exchange server that is on a Comcast network. While my actual IP > is not listed, the block of 68.52.0.0/16 is listed on > http://mail-abuse.org/dul/ . Is there a way around this? About 1/2 of the > mail I send out is coming back. You are experiencing the very issue why I am adamantly against using a lpr4 test to block messages. Using them in a weighting system is fine. One suggestion if you can not change ISP, and the ISP does not care to help you with this, is to use a gateway service that is not list. Therefore, all of your messages would be seen coming from a clean IP address. If you need quick help and are in a bind, contact me off list. John Tolmachoff MCSE CSSA Engineer/Consultant eServices For You www.eservicesforyou.com