If customer tries to use the Type a name section in the Communicator client to try and locate a person not yet added as a contact, they only get a result if they type in the full SIP address (i.e. firstname.lastname@example.org). Typing in first names or display names, etc, does not yield a match.
ResolutionCheck and modify if needed the value of the attribute RtcAbIndexAttributeList in Address Book configuration file on Microsoft Office Communication (OCS) Front End Server - C:\Program Files\Microsoft Office Communications Server 2007 R2\Server\Core\ABServer.exe.config. If you have several Front End servers in pool apply changes on all of them.
If you want to enable search by first/last names then you need to add corresponding parameters in value of the attribute RtcAbIndexAttributeList - givenName (First Name) and sn (Last Name) like in the example below:
<add key="RtcAbIndexAttributeList" value="givenName,sn,displayName,mailNickname,
If you updated the configuration file then address list has to be updated with the help of ABServer.exe -syncNow command.
There is the following note for the operation syncNow in Microsoft TechNet article http://technet.microsoft.com/en-us/library/bb936631%28office.12%29.aspx:
Manually synchronizes the Address Book Server by pausing the service to perform synchronization and then restarting the service. If you are in a failover scenario and failing over from one server to another and syncNow does not work, check the load-balancer settings. The health monitor for incoming port 135 should point to 5060 (or 5061) on the servers. By default, it will point to 135 on the servers and since 135 is always up when the computer is running the server remains marked as being up even though Office Communications Server Front End service is down.
So, keep in mind that Address Book service will be stopped during synchronization.