Securing Groups

Administrators will want to secure the messaging environment by securing distribution and mail-enabled security groups. Exchange 2003 provides a simple way to configure messaging restrictions for a distribution group. Use the following steps to secure distribution groups so that only authenticated users are allowed access:

1.	In Active Directory Users and Computers, right-click the distribution group to work with and select Properties.
2.	Click the Exchange General tab. In the Message Restrictions section, click the From Authenticated Users Only check box.
3.	Click OK when finished.

Administrators can add more restrictions to a group by allowing only a specific security group to access it. Use the following steps to restrict distribution group access to specific groups or users:

1.	In Active Directory Users and Computers, right-click the distribution group to work with and select Properties.
2.	Click the Exchange General tab. In the Message Restrictions section, click the Only From option button.
3.	Click Add and enter the security group that has permission to send messages to the distribution group. Click OK and then click OK again to finish.