If you are using the built-in SmarterMail spam tests, then make certain you have both your SMTP and DELIVERY logs set to DETAILED.
When something is marked as SPAM, then search the delivery logs for the SENDER'S e-mail address with the DISPLAY RELATED TRAFFIC box checked:
and you will find all of the spam filters which were tested, and/or, triggered, by the incoming tests.
To further assist you in making certain you are checking and filtering all the possible spam, see the most current version of the following, and assist you in overcoming delivery denial by YAHOO!, G-Mail, Comcast, AOL, and most of the other large ISPs see the following documents which I have published:
Bruce Barnes
Bruce Barnes
ChicagoNetTech Inc
brucecnt@comcast.net
Phonr: (773) 491-9019
Phone: (224) 444-0169
E-Mail and DNS Security Specialist
Network Security Specialist
Customer Service Portal: https://portal.chicagonettech.com
Website: https://www.ChicagoNetTech.com
Security Blog: http://networkbastion.blogspot.com/
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