How to Add Recipients to the Recipient Block List
Microsoft Exchange Server 2007 will reach end of support on April 11, 2017. To stay supported, you will need to upgrade. For more information, see Resources to help you upgrade your Office 2007 servers and clients.
Applies to: Exchange Server 2007, Exchange Server 2007 SP1, Exchange Server 2007 SP2, Exchange Server 2007 SP3
This topic explains how to use the Exchange Management Console or the Exchange Management Shell to add recipients to the Recipient Block list for recipient filtering. You can configure recipient filtering to block inbound messages for up to 100 specific recipients in your organization. If an inbound message contains a recipient that is on the Recipient Block list, the computer that has the Edge Transport server role installed sends a "550 5.1.1 User unknown" Simple Mail Transfer Protocol (SMTP) session error to the sending system.
The Recipient Block list reads from a recipient information cache on the local Edge Transport server. The recipient information cache is updated every four hours. Therefore, if you add recipients to the Recipient Block list, it may be up to four hours before the recipient information cache is updated. To update the recipient information cache immediately after you add recipients to the Recipient Block list, restart the Microsoft Exchange Transport service on the Edge Transport server on which recipient filtering is being run.
Before You Begin
To perform the following procedures on a computer that has the Edge Transport Server role installed, you must log on by using an account that is a member of the local Administrator's group on that computer.
Also, before you perform these procedures, confirm the following:
You have reviewed Anti-Spam and Antivirus Functionality to understand the general strategy for configuring all anti-spam agents so that they work together efficiently for your organization.
You have read Recipient Filtering.
To add recipients to the Recipient Block list by using the Exchange Management Console
In the Exchange Management Console, click Edge Transport.
In the work pane, click the Anti-spam tab, and then select Recipient Filtering.
In the action pane, select Properties, and then on the Recipient Filtering Properties page, click the Blocked Recipients tab.
To automatically block messages to recipients that do not exist in your organization or recipients that require sender authentication, select the Block messages sent to recipients not listed in the recipient list check box.
For more information about how to require sender authentication, see How to Configure Anti-Spam Features on a Mailbox.
To enable recipient blocking, select the Block the following recipients check box.
In the text box, type the SMTP address for a recipient, and then click Add to add that recipient to the Recipient Block list.
Click OK to save your changes and close the dialog box, or click Apply to save your changes without closing the dialog box.
To add recipients to the Recipient Block list by using the Exchange Management Shell
To enable recipient blocking, run the following command:
Set-RecipientFilterConfig -BlockListEnabled $true
To add recipients to the Recipient Block list, run the following command:
Set-RecipientFilterConfig -BlockedRecipients <SMTPAddress>
For example, to add firstname.lastname@example.org to the Recipient Block list, run the following command:
Set-RecipientFilterConfig -BlockedRecipients email@example.com
You can add multiple recipients by putting a comma between each SMTP address. For example firstname.lastname@example.org, email@example.com. The BlockedRecipients parameter takes multiple values. When you pass a value to the BlockedRecipients parameter, the existing value is replaced with the new value. For more information about how to add or remove values from multivalued properties, see Modifying Multivalued Properties.
To block messages to recipients that do not exist in your organization, run the following command:
Set-RecipientFilterConfig -RecipientValidationEnabled $true
For detailed syntax and parameter information, see Set-RecipientFilterConfig.
For More Information
For more information about how to configure recipient filtering, see the following topics: