Blacklists
You can add e-mail addresses to a list of people you never want to pass the spam filter.
There is one way of blacklisting a sending address.
Go to the “PREFERENCES” tab.
Select the “Whitelist/Blacklist” option.
In the “Blocked Email Addresses and Domains (Blacklist), enter addresses of senders you wish to blacklist.
E-mail from that address will always be blocked with a message returned saying they were blocked.

If you have any questions feel free to call or e-mail support for assistance.