The dynamic IP block list is a public block list that contains information about known spammers. The AntiSpam service uses the dynamic IP block list as part of its protection.
To enable the use of a public block list
Select Services > Email Services > Anti-Spam.
Click the Detection Settings tab.
In the Responsive Spam Detection area, check the Dynamic IP public block list box.
Specify an Action from the drop-down list, to be used for any emails sent by senders on the public block list.
Click Save and Exit.
A confirmation of the settings is displayed.