I realized recently that Spamhaus.org had discontinued its use of the spam protection parameters set within HMailServer based upon “DNS” errors I started seeing in my log files. It made no sense. So I went to their site and did some investigating and found they have consolidated the three spam databases into one, called “zen.spamhaus.org”.
So within your HMailServer admin console, go in and delete the current spamhaus.org configurations you have in place (should only be two). Then add a new “DNS Blacklist” with the following parameters: for the “DNS host” enter “zen.spamhaus.org”; for the “Expected result,” enter “127.0.0.*”; and then for the “Rejection Message” enter “Rejected by Spamhaus”. It appears to have cut down spam even more since I have set this. About 5-10 messages a day were getting through before and now none are (so far at least).