Switching On Spam Protection Based on DNS Blackhole Lists
You can use free and paid subscription blackhole lists with your server. Visit http://spamlinks.net/filter-dnsbl-lists.htm and choose a DNSBL server you want to use.
To switch on spam protection based on DNSBL:
- Click the Server shortcut in the navigation pane.
- Click the Mail icon in the Services group.
- Select the Switch on spam protection based on DNS blackhole lists check box.
- In the DNS zones for DNSBL service input box, specify the host name that your mail server should query, for example: sbl.spamhaus.org.
- Click OK.
Now, e-mail messages from known spammers should be rejected with an error code 550 (connection refused).