I send lot of emails. Couple years ago sending emails was lot easier! But I got nothing to do, I have to adapt with it! Am confused! Am trying to figure out how does SpamHaus blacklist works! Am using PMTA as SMTP gateway to manage the sending from 64 IPs and 1 domain to send emails. but after each sending all the IPs get listed in SpamHaus CSS. Once get listed on SpamHaus, Major ESP will reject my emails! I tried to send from 63 instead of 64, all the 63 were listed again except the one I isolated (did not configure it to send emails).. After doing some researches I found that spamhaus is design to list all the senders that using many IPs and domains to send emails, I figured that maybe SpamHaus can know how many IPs are sending the same campaign. then list them all. using spam traps!!!? Later then! I separated the IPs in an attempt to isolate the sending. I used 9 new domains. (7 Domains for for 64 IPs each domain used to config 10 IPs and 2 domains for the rDNS). Then, I slowed the software to send the exact number of emails PowerMTA can handle at the time (So emails wonâ€™t queue up on PowerMTA and the recipients wonâ€™t receive the emails in long time delay). So I was rotating IPs domains and SMTPs. In that test some of the IPs got lists and some were clean. I still have not got the chance to test test rotating subjects and contents along will the previous test ( rotating IPs domains and SMTPs). Am still trying to figure out how does spamhaus list IPs. and how other senders with /23 and /24 ..etc manage to avoid spamhaus, and stay out of their radar!!? Thanks a bunch!