You can add names, email addresses and domains to these lists so the filter doesn’t check messages from sources you trust, or blocks messages that arrive from specific email addresses and domains you don't know or trust. Safe Senders list: Email addresses and domain names in the Safe Senders List are never treated as junk email, regardless of the content of the message. You can add your Contacts and other correspondents to this list. If you use a Microsoft Exchange Server account, all names and addresses in the global address list (GAL) are automatically considered safe. The Safe Sender limit is 1024. Safe Recipients list: If you belong to a mailing list or a distribution list, you can add the list sender to the Safe Recipients List. Messages sent to these email addresses or domain names are never treated as junk, regardless of the content of the message. Blocked Senders list: You can easily block messages from particular senders by adding their email addresses or domain names to the Blocked Senders List. When you add a name or email address to this list, Outlook quarantines any incoming message from that source. Messages from people or domain names that appear in this list are always classified as junk, regardless of the content of the message. The blocked sender limit is 500. Blocked Top-Level Domains list: To block unwanted email messages from another country/region, you can add country/region codes to the Blocked Top-Level Domains List. For example, checking the CA [Canada], US [United States], and MX [Mexico] boxes in the list blocks messages from email addresses that end in .ca, .us, and .mx. Blocked Encoding list: To block unwanted email messages that appear in another character set or alphabet, you can add encoding to the Blocked Encoding List.