Article ID: 2649727 - View products that this article applies to.
Consider the following scenario:
Note When this issue occurs, the Exchange Server 2010 users cannot access their mailboxes.
This issue occurs because all threads used by the RPC Client Access service are blocked on requests to the problematic Mailbox server.
To resolve this issue, install the following update rollup:
(https://support.microsoft.com/kb/2645995/ )Description of Update Rollup 1 for Exchange Server 2010 Service Pack 2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about the RPC Client Access service, visit the following Microsoft website:
General information about the RPC Client Access service
Article ID: 2649727 - Last Review: February 13, 2012 - Revision: 1.0