Greetings, I am running a FC4 sendmail server and I've been trying forever to at least limit some of the spam. In this effort, I have been adding to the Access control (/etc/mail/access) domains that are known to be mail bombing my domain. A few continue to evade the sendmail filtering and are still getting through. I know this because LogWatch reports: Unknown Local Users invaliduser@xxxxxxxxxxxx from *.speedy.net.pe ... (may be forged) where * contains the specific client that continues to change. My first attempt to block them, I added to /etc/mail/access speedy.net.pe REJECT to try and reject the problem domain. This doesn't work because LogWatch continues to report to me that mail is coming in. I've tried to reject on the IP as follows: 201.230.19.113 REJECT but of course, they just changed IP address. Can anyone explain to my the whole in my security that is allowing them to get through and how to plug it? Thank you in advance.