Quick update – ‘Learn FP’ folder adjustment
Some of you may have noticed lately that the ‘Learn FP’ mail folder has been a little less reliable lately. If you got a message that was incorrectly flagged as Spam and dropped it into ‘Learn FP’, it might end up back in your Spam folder. I’ve addressed this and it should not happen again – instead the message will be delivered to your inbox.
The reason for the odd behavior is simple if you follow what’s going on behind the scenes. The ‘Learn FP’ folder gets scanned periodically by a job on one of the mail servers. This job removes the markup from the message and queues it for redelivery, but during redelivery SpamAssassin scans the message again. Previously, when we were using SpamAssassin’s Bayesian filter, we’d also process the message as ‘ham’ to train the filter. Then when redelivery happened, SpamAssassin would scan the message and generally not re-mark it as Spam due to the new information it had from the learning process (though it still did mark things wrong rarely). Since we stopped using the bayesian filter the spamassassin scans are more consistent, so once spam, always spam. The adjustment I made was simple – skip SpamAssassin on redelivery and just go straight to the inbox.