Trusted Senders
This setting allows users to list specific email addresses (such as jsmith@example.com) or domains (such as example.com) that will be exempted from spam filtering. Email addresses or domain names can be added to your list of trusted senders. This can prevent mail from friends, business associates, and mailing lists from being blocked and lets the system know that these messages come from a trusted source. Note: The email address for messages that you unmark as spam are automatically included on your trusted senders list.
To view your trusted senders list, click the Settings button in the main toolbar and then click the Settings navigation pane. Then expand the My Settings folder and click Trusted Senders in the left tree view. When adding a new trusted sender to the list, make sure to type only one email address of domain per line.