Spam Assasin (100% Customizable) Does not delete any of the incoming emails. If just flags them as potential spam. It is then up to yoou to filter then on your local machine to identify them appropriately.
I have my mail software to put anything that scores higher than 5 points using Spam Assasin to be put into a sepereate folder which I glance through whenever I get new email just to double check, before I delete it all. So far I have received 0 messages in my Spam box that shouldn't have been there. The odd one slips by to my inbox, but its only a few a week instead of hundreds!
Once again, you can completely control wether Spam Assasin is enabled, and what it filters, and if you want you can set up a special whitelilst that allows certain people to get through the filter system no matter how much of a spam the message looks like.
- Ed
