The Safe Recipients List helps fine-tune the filter's understanding of what's junk and what's not.
You may wonder why the filter includes a Safe Recipients List. Here's why:
Sometimes, you receive a legitimate message where your name is not on the To line, but only on the Cc or Bcc line. Other times, a legitimate message may be addressed only to a group to which you belong, so that your personal name or address doesn’t appear at all.
Outlook often identifies such messages as junk, because this is one way that people can try to send you spam. The Safe Recipients List is a handy way to help Outlook identify when these sorts of messages are probably not junk after all.
Outlook treats a distribution list name, such as "NewsletterDL@contoso.com", as a recipient. So if you add that address to the Safe Recipients List, all messages addressed to that list go to your Inbox, even when you are not the only recipient — and even if you aren't personally named as a recipient at all.
In the same way, if your name appears only on the Cc or Bcc line of legitimate messages addressed to a different person, then adding that person to your Safe Recipients List will help prevent the filter from deciding that the message is spam and sending it to your Junk E-mail folder.
Tip This probably sounds odd, but don't add your own e-mail address to the Safe Recipients List. Junk senders often get hold of personal details, including addresses, and just because a message is addressed to you doesn't always mean it's legitimate.