To add someone to your "Blocked Senders" list in Office 365, please follow the procedure below:

  1. Login to Office 365 at
  2. Click the gear icon in the upper right corner and then click "View all Outlook settings". This will open the "Settings" pane.

  3. In the "Settings" pane, under "Mail" click "Junk email". This will open the "Junk email" pane.

  4. Under "Blocked senders and domains" click "Add" , type in the email address or domain to block, and press Enter.

    5. Click on the "Save" button that appears at the bottom of the screen.