Configuring recipient verification in Exchange 2007 / Exchange 2010

PROBLEM:

Libra Esva needs to be able to verify whether or not an email address points to a valid recipient. One method is by integrating with an LDAP server. A second method is through dynamic recipient verification. A third method is manually listing the valid email addresses. The first two methods are completely automatic and therefore preferred.

SOLUTION:

This article describes how to setup recipient verification in Exchange 2007 servers. In Exchange 2007 and 2010, recipient verification is part of what Microsoft calls “Anti-Spam Features.” If you only have a single Exchange server, then you will need to follow these steps to activate the Anti-Spam Features on your Exchange server in order to activate recipient verification. Follow the steps below to accomplish this.

Configuration Steps

First, install the Anti-Spam Features on your Exchange server (for more information, see the TechNet article for Exchange 2007 or Exchange 2010):

1. Run the PowerShell script (note that it ends in the number 1, not the letter I or L):
   \Program Files\Microsoft\Exchange Server\Scripts\InstallAntispamAgents.ps1 (Exchange 2007)
   \Program Files\Microsoft\Exchange Server\V14\Scripts\InstallAntispamAgents.ps1 (Exchange 2010)
2. Restart the Microsoft Exchange Transport service:
   In a PowerShell prompt: Restart-Service MSExchangeTransport

Next, enable the Recipient Filtering feature:

1. Open the Exchange Manager user interface and go to Organization Configuration -> Hub Transport.
2. In the Anti-spam tab, enable Recipient Filtering.
3. In the properties dialog for Recipient Filtering, in the Blocked Recipients tab, enable Block messages sent to recipients not listed in the Global Address List.
4. Restart the Microsoft Exchange Transport service (again).