Article ID: 2549052 - View products that this article applies to.
The following event is logged in the Office Communications Server log on a Microsoft Office Communications Server 2007 R2 Group Chat server.
Log Name: Office Communications Server
This issue occurs if you create a user in the Active Directory directory service who has a distinguished name of more than 256 characters, and then you add this user to a distribution group.
To resolve this issue, install the following cumulative update:
(http://support.microsoft.com/kb/2549044/ )Update package for the Office Communications Server 2007 R2 Group Chat server: June, 2011
Note After you apply this update,the Group Chat server supports up to 384 characters in the distinguished name.