Hi Chirpy... I have implemented many of your server suggestions including mailscanner, etc. Recently I created a new e-mail account via cpanel and did some testing. I am getting a unusual bounce and hope you can point me the right direction as I looked at several files and don't see why this is not geting through. Below is what I get returned to my sending e-mail address. I have changed the addresses for public use... *** ----- The following addresses had permanent fatal errors ----- <email@example.com> (reason: 550-X-RBL-Warning: 220.127.116.11 is in a blacklist at spam.dnsbl.sorbs.net.) ----- Transcript of session follows ----- ... while talking to mydomain.com.: >>> DATA <<< 550-X-RBL-Warning: 18.104.22.168 is in a blacklist at spam.dnsbl.sorbs.net. <<< 550 http://www.dnsbl.us.sorbs.net/cgi-bin/lookup?js&IP=22.214.171.124 550 5.1.1 <firstname.lastname@example.org>... User unknown <<< 503 valid RCPT command must precede DATA *** It appears the IP 126.96.36.199 is one of the servers from my ISP (RoadRunner) that passes the message to my server, and my server is not accepting the message. I checked my rules list bit don't see that I am using sorbs.net for blacklists. So it must be in a file I am not seeing. Anything else you can tel me about the above error? I can send e-mail to the new address from several other accounts, even gmail and hotmail that sometimes get blocked. Thanks in advance for any input.