1. Go to the "Home" tab in Outlook, click the "Junk" drop-down, and then click "Junk E-mail Options..."
A "Junk Email Options" window will open:
2. In the "Safe Senders" tab, make sure the email domains you want to allow are present, and make sure "Also trust email from my Contacts" is checked.
3. In the "Safe Recipients" tab, make sure the email domains you want to allow are present.
4. Make sure the domains you want to allow are not present in the "Block Senders" tab, and make sure the domains you want to block are present.