Bill,

All the white lists are checked first. If a match is found, the blacklists are skipped, the email recipients are accepted, and SpamFilter is ready to accept the data command. If none of the whitelists are matched, then the blacklists are currently searched in order below. This order is not user-definable, at least not right now.

1. Allowed Domains
2. Local Domain BlackList
3. Local Emails Blacklist
4. Local Emails TO Blacklist
5. Not in Authorized TO Emails
6. Country Blacklist
7. Reject No Reverse DNS
8. Reject Empty Mail From
9. Reject Same To From Email address
10. Reject Same To From Domain
11. Recipient Count > Max RCPTTO
12. MAPS check
13. Keywords
14. Bayesian Filtering

The only exception to the whitelist is the "whitelist keyword check". In order for that to work, the message has to be received first, and for this reason even if the senders is blacklisted by other filters, the email will still be received so that it can be checked against the keyword whitelist.

Once a blacklist "hits", all further blacklist checks are skipped.

Roberto F.
LogSat Software