Once the Realtime Domain Whitelist has been checked, Connection Checks will then continue validation checks for Realtime Domain Blacklists and Verification Checks (if enabled).
The Administrator also controls whether the message should be deleted, dropped or only add an X-Header.
The action "Only Add X-Header" allows Administrators to test and review messages that have matches from the Realtime Domain Blacklists or failed Verification Checks that were set. An X-Header is inserted in the message for every match made to a realtime domain blacklist or failed verification check. The e-mail is then passed on to content filtering for further examination. The message is delivered if no other rules processing takes place.
For the action "Reject Connection" and "Delete Message" each spam database listed in the Realtime Domain Blacklist that identifies the sender as spam counts as a match and each validation check failure counts as a match. The Administrator must decide at what point the total match count necessitates action to be taken. See Examples.
Note: Realtime Domain Blacklists are not enabled by default.
Important: Realtime Domain Blacklists can only be added after the Realtime Blacklist at the system level is setup.
Caution: A match made for a Trusted blacklist will immediately either delete or reject the message (includes action Only Add X-Header) depending on the Verification Checks setting for Blacklists.