Outbound spam issue
Posted on 2010-11-22
After hours, the mail server is being hit with thousands of outbound spam messages coming from postmaster@domain. Postmaster does not exist. It's reaking havoc on our network, causing us to be blacklisted etc. I have scanned every pc, checked for open relay, firewall is configured for all outbound smtp traffic to go thru mail server. No matter what, mail keeps flooding network, usually after 5pm and on weekends.