This section describes the blacklist actions available for the On Arrival filtering point.
Find the related configuration options under by clicking the Edit button under On Arrival.
ORF provides four blacklist actions at the On Arrival filtering point. These actions are performed when the email is blacklisted, e.g., due to a DNS blacklist or keyword filter hit.
You can choose to reject the email on blacklist hit, or accept it and perform further actions, like tag the email subject, tag the email header, or redirect the blacklisted email to a specified email address. The latter three actions can be combined (e.g., you can tag the subject and redirect the blacklisted email at the same time).
If you decide to reject the email, senders will get notified about the failed delivery, because their email server will send a bounce report to them.
Click the SMTP Response button to edit the SMTP response returned to the sender server upon rejection. More about SMTP responses is available in the SMTP Responses section of the help.
In contrast with rejecting the email, if you decide to accept the email and perform further actions, the selected action(s) will be performed on blacklisted emails. Senders will not get notified about these actions, as their emails are not rejected.
When this action is selected, the blacklisted email is accepted, but the subject line is tagged with a customizable text (Subject Tag), either on the left or on the right side (Tag on the left / right side).
As the email is accepted, no bounce report is generated. The recipient can use automatic email rules to move the tagged email to a separate folder, e.g., Spam (both Microsoft® Outlook® and Outlook® Express support these kind of rules).
The subject tag is Unicode-supported.
You can combine this action with tagging the email header and email redirection.
If you have Exchange 2003 SP1 or above, you can use subject tagging to redirect blacklisted emails to the Junk folder of each recipient for further review. For more information, read our article.
Select this action to accept the blacklisted email and add a custom tag to the email header. As the email is accepted, no bounce report is generated. The recipient can use automatic email rules to move the tagged email to a separate folder, e.g., Spam (these kind of rules are supported by Microsoft® Outlook®, but Outlook® Express cannot check the email header for rules). You may add the {TESTNAME} special field to the header tag (click the right side of the header tag box), which will be replaced by the name of the actual blacklist test that triggered the filtering action.
You can combine this action with tagging the email subject and email redirection.
Select this action to accept the blacklisted email and redirect it to another recipient. As the email is accepted, no bounce report is generated. The original recipient does not get the email (except if the recipient is the redirection address, of course).
You can combine this action with tagging the email subject and the header.
Tarpit delay holds back SMTP responses sent by ORF upon blacklisting. As the sender server has to wait for the each response, you can use this feature to "fight back" spammers by slowing them down or to make it virtually impossible for them to carry out a successful Directory Harvest Attack (DHA).
For more information, please see the Tarpit Delay Settings section.
The On Arrival actions do not apply to the Attachment Filtering, the Recipient Blacklist, the Recipient Validation, DHA Protection and the External Agents tests. The Attachment Filtering test has its own actions, such as to replace the attachment with a warning text or drop the entire email. The Recipient Blacklist, Recipient Validation and DHA Protection tests work with recipients rather than emails, so different actions are used (e.g., it would be problematic to tag the email subject and deliver the blacklisted email to the intended recipient when the recipient does not exist). The External Agents feature gives you a finer control of the actions.