With Communicator Web Access, users can use an Active Directory distribution group as a contact. This makes it easy to send an instant message (IM) to all the members of that group. Users can simply direct the message to the group rather than to each individual member of the group.

Communicator Web Access also supports distribution group expansion. When distribution group expansion is enabled users can use a distribution group as a contact. In addition to that, users can “expand” the membership list for that group. This enables them to see all the members of that group, along with their individual contact and status information. Because of this, you can work with the group as a whole, or you can work with each of the individual members of that group.

To enable distribution group support

Distribution group expansion is configured at the pool level (for Enterprise Edition) or at the server level (for Standard Edition), and the configured setting applies to both Communicator Web Access and Office Communicator. By default, distribution group expansion is enabled when you install Office Communications Server. You can verify (or, if necessary, change) these settings by doing the following:

To enable distribution group support

  1. Log on to a computer running the Office Communications Server administrative tools. To enable distribution group support you must be a member of both the Domain Administrators group and the RTCUniversalServerAdmins group.

  2. Click Start, point to Administrative Tools, and then click Office Communications Server 2007 R2.

  3. In the console tree, expand the forest node.

  4. Do one of the following:

    • If you are running Office Communications Server Enterprise Edition, expand Enterprise pools, and then right-click the pool in which Communicator Web Access is installed.

    • If you are running Office Communications Server Standard Edition, expand Standard Edition Serversand right-click the name of the server on which Communicator Web Access is installed.

  5. Click Propertiesand then click Web Component Properties.

  6. In the Web Components Propertiesdialog box, on the Address Booktab, verify that Enable distribution groups expansionhas been selected, and that the desired value has been entered in the Maximum group sizebox.

  7. Make any changes as needed, and then click OK.