Article ID: 2794253 - View products that this article applies to.
Consider the following scenario:
This issue occurs because the DSProxy component does not support connections that use the IPv6 protocol in the scenario that is described in the "Symptoms" section. Therefore, the DSProxy component cannot resolve Outlook clients.
To work around this issue, use one of the following methods.
Method 1Install the Client Access role and the Mailbox role on different member servers.
Method 2Disable IPv6 on only the Exchange Server 2007 member server that has the Client Access role and the Mailbox role installed. For more information about how to do this, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/929852/ )How to disable IP version 6 or its specific components in Windows
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.