Restricting users from receiving internet mail outside of your company

Blocking a user from receiving Internet based mail is much simpler in Exchange 2003 because our good friends at Microsoft included a simple checkbox, so here are the steps you can take:

  1. Open the properties for the user that you want to stop receiving Internet mail in Active Directory Users and Computers.
  2. Select the Exchange General tab, and then click on the Delivery Restrictions button, the Delivery Restrictions dialog box will now appear.
  3. Check the “From authenticated users only” checkbox in the Message Restrictions section.

Read the rest of the article here.