Exchange 2007 Distribution Groups

Before Microsoft Exchange Server became so closely connected to Active Directory (AD), administrators had to use static distribution lists to manually handle list memberships. Starting with Exchange Server 2000, AD was directly integrated into Exchange. Exchange Server 2003 saw the creation of distribution groups (and query-based distribution groups), which are populated by static memberships. Exchange Server 2007 introduced dynamic distribution groups, which are defined by filters and conditions each time a message is sent to the group. In this article I explain how to create traditional static distribution groups and Exchange 2007 dynamic distribution groups.

Types of Distribution Groups
Whether you create your own distribution groups, or they are pulled from a previous version of Exchange during a migration, four distinct types of distribution groups exist (beyond what you might think of as simply static versus dynamic groups). Exchange Management Console (EMC) displays these four types of distribution groups and represents each with a separate icon.

• Mail-enabled universal distribution groups—AD distribution group objects that are mail-enabled; their sole purpose is to distribute messages to a group of recipients.
• Mail-enabled universal security groups—AD security group objects that are mail-enabled; they can be used to grant access permissions to resources in AD, as well as to distribute messages.
• Mail-enabled non-universal groups—carryovers from migrated mail-enabled groups from previous versions of Exchange. (In Exchange 2007, you can create or mail-enable only universal groups.) Although EMC shows mail-enabled non-universal groups, the actual administration you can perform on them is limited. Because maintaining non-universal groups can create problems with membership expansion, you should switch to universal groups if possible.
• Dynamic distribution groups—offshoots of Exchange 2003’s query-based distribution groups. In Exchange 2003’s query-based groups, you provide an LDAP query to dynamically build membership. In Exchange 2007, membership is based on specific recipient filters rather than a defined set of recipients.

Creating a Traditional Distribution Group
To create a new distribution group, perform the following steps:

1.     Open EMC.

2.     From the navigation tree in the left-hand pane, select the Recipient Configuration container and click Distribution Group.

3.     In the Actions pane you’ll see two options for creating distribution groups: New Distribution Group and New Dynamic Distribution Group. Select New Distribution Group.

4.     The wizard’s Introduction dialog box gives you the option of creating a distribution group for a new or existing group. If you have an existing universal security group that isn’t mail-enabled, you can browse to the group and configure it as a Mail-Enabled Universal Security Group. You can also create a new distribution or security group. If you don’t have the administrative permissions to directly create a security group or handle its membership, you can work with your AD administrators to ensure that the group exists on the AD side, then use EMC to mail-enable the group on the Exchange side. In this case, select New Group.

5.     In the Group Information dialog box, which Figure 1 shows, enter the following information:

a.     Group type: Select Distribution

b.    Organizational unit: Browse to select a location

c.     Name: Enter the group name, which can’t exceed 64 characters

d.    Name (pre-Windows 2000): Because of legacy naming, this name is automatically populated by the Name field and should be correct.

e.     Alias: By default, the alias is the same as the distribution group’s name. You can change the alias, which you might do if you want to give the group an alternative name (e.g., if you want the alias to be unique compared with the AD-oriented security group). Like the name itself, the alias can’t exceed 64 characters. In addition, the alias must be unique within the forest.

f.     Click Next when you finish entering information in the Group Information dialog box.

6.     In the New Distribution Group dialog box that opens, review the configuration summary to confirm the information, then click New.

7.     Once the group is created, you’ll see a Completion screen with a green check mark that says Completed. Click Finish.