This very comprehensive article describes all methods used to stop spam and relay mail. There are a number of approaches that can be used to limit spam traffic coming into your organization using the features available in MAILsweeper version 4. Restart the SMTP Receiver service. This causes MAILsweeper to check mail hosts, using a DNS query to the Internet, against the Real Time Blacklist, which is a managed database of hosts renowned for the proliferation of nuisance email, for example, junk mail or Spam.
Any match rejects the incoming mail.
All messages from that address will be rejected with SMTP error 550. SMTP Relay Right click and select Properties. In all versions of MAILsweeper this is not relayed to spamtarget, but to the mail server for your domain, which should normally eject it. If there is no quarantine action the message will be deleted. If your MAILsweeper is configured to accept mail for additional, or alias, domains, create a pair of entries for each additional domain in this address list.