1. Begin by opening up Windows Live Mail 2011. Click on the "Windows Mail" button and select "Safety options..." from the "Options" menu.
  2. The "Safety Options" window will now appear. Select the "Blocked Senders" tab.
  3. To add an email address to the blocked senders list click "Add...".
  4. Type in the email address or domain address you would like to block and click "OK".
  5. When you are finished adding email addresses or domains to your blocked senders list click "OK" to close the "Safety Options" window.