Consider the following scenario:
- You have a member server that has the Microsoft Exchange Server 2007 Client Access role and the Mailbox role installed.
- The server is not a global catalog server.
- Internet Protocol version 6 (IPv6) is enabled on the server.
- This issue does not occur in single-role Exchange Server 2007 deployments where the member server has only the Client Access Server role installed.
- This issue also occurs when you use Outlook Anywhere externally in an Exchange Server 2007 and Exchange Server 2013 coexistence environment.
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:
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.