Terry,
We finished debugging your logfile, and I have to agree that the spam catch accuracy is not as good as we're used to seeing.
The logfile you forwarded us shows 44,302 connection attempts. Of those connections, SpamFilter accepted and delivered only 7,337 emails. 758 of these emails were whitelisted, so SpamFilter identified as clean 6,579 emails out of 44,302. This means that SpamFilter only allowed 14.9% of your total email traffic thru. Not counting the whitelisted emails, SpamFilter thus identified as spam about 85.1% of your total SMTP traffic. This is actually slightly better than the 70%-80% we usually see.
Now, assuming that one out of two emails you receive in your mailbox is spam (thus 50%), this still means that SpamFilter incorrectly allowed thru 50% x 6,579 = 3,290 emails. So SpamFilter would have incorrectly identified as clean only 3,290 emails out of 44,302. This is an accuracy of 92.6%, which is instead slightly lower from the 95%-99%% accuracy we often see.
The one filter that usually catches more spam than what we see in your logs is the MAPS RBL filter. That filter blocked only 1,652 emails that day. That is rather low when comparing it to our own proprietary SFDB filter that blocked 8,121 of your emails.
I'd suggest removing these entries from your MAPS server list as they did not block a single email:
combined.njabl.org, true zombie.dnsbl.sorbs.net, true
and replacing them with these ones:
dnsbl-2.uceprotect.net, true ubl.unsubscore.com, true free.v4bl.org, true
to see if that filter improves a bit.
------------- Roberto Franceschetti
http://www.logsat.com" rel="nofollow - LogSat Software
http://www.logsat.com/sfi-spam-filter.asp" rel="nofollow - Spam Filter ISP
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