How an Email Message is Processed by SmarterMail

There is a certain "order of operations" for how a message is processed by SmarterMail. Below is a list of the processes that run against a message as it enters or leaves the Spool of a SmarterMail server. Where add-ons are listed, those are only run against a message if they're actually in use. Other options, such as command line checks or various spam checks, are only used if they're enabled:

  1. Clam Antivirus
  2. Cyren Antivirus
  3. Command line checks (antivirus, etc.)
  4. File type checks (allowed attachments, etc.)
  5. Spam checks, in order:
    1. rDNS
    2. Null Sender
    3. HoneyPot
    4. Cyren Antispam
    5. MessageSniffer
    6. Internal SpamAssassin
    7. Remote SpamAssassin
    8. SPF
    9. DKIM
    10. Custom body rules
    11. RBLs
    12. URIBLs
  6. Email archiving (if enabled)
  7. Content filters (content filters run in the order they're added, from top to bottom)
Regarding spam checks, all of the spam checks are run against every message unless the sending IP address is whitelisted. In the case of Trusted Senders, any spam scores EXCEPT for DKIM and SPF are zeroed out  -- DKIM and SPF are still scored to help prevent spoofing of FROM addresses.