Blacklisting ensures that certain "unwelcome" email addresses or domain names will be blocked from receiving emails from your GetResponse campaign.
You can blacklist a particular email address of the whole domain name
by entering e.g. @domainname.com (you must include the @ sign)
so that they will not be able to subscribe to your campaign. All addresses
(but not the domain names) will be also removed from your Subscribers
and Active Subscribers lists.
This can be done under Subscribers >> Deleted Subscribers >> Blacklist.