Blocked Senders List

You can easily block messages from certain e-mail address or domain name by adding the sender to this list. Messages from people or domain names on this list are always treated as junk e-mail messages, regardless of the content of the message. When you add a sender's name or e-mail address to the Blocked Sender's List, Outlook moves the message to the Junk E-mail folder.

E-mail domain addresses (ex: @microsoft.com) on the list are never treated as junk e-mail and are automatically delivered to the Inbox.

Safe Recipients List   

Add the names of your distribution lists to the Safe Recipients List so any messages sent to these e-mail addresses or domain names will never be treated as junk e-mail messages. Do not add the names of distribution lists found on the RC Global Address list; by default they are considered safe senders.