During a migration to Exchange 2007, one of the often overlooked steps is the upgrade of the E-mail Address Policies. Remember that these policies need to be upgraded before they can be modified or really even viewed in the Exchange Management Console.

1. Open the Exchange Management Shell
2. To view the policies:  get-EmailAddressPolicy
3. To upgrade the default policy:  set-EmailAddressPolicy "Default Policy" -IncludedRecipients AllRecipients
4. Depending on the filtering parameters of the remaining policies you can continue to use this command.  However, if the other policies contain advanced LDAP queries you will want to review the Exchange Team Blog.