I have a mail gateway running exim (originally from Cambridge University), spamassassin (from the apache organisation) and clam antivirus (from Cisco) which between them are blocking over 50 emails per day at present, and if very sure that it is spam will keep the senders hanging around until they abandon delivery. All I see in the rejection log is a selected part of the header which can be used for identification. Any emails that are suspicious but not definitely junk are marked with a warning. This is running Free Open Source Debian Linux on a RaspberryPi credit card size computer, as being used to teach school children. Any junk which is allowed through is passed back so that the system can learn about my likes and dislikes.Linux systems are designed to be as secure and reliable as possible, so are very difficult to corrupt.Website http://chrisbell.org.uk
Christopher Bell ● 3134d