Users cannot access Outlook mailboxes that connect to a Client Access server array in an Exchange Server 2010 environment

Á við um: Exchange Server 2010 Service Pack 3Exchange Server 2010 EnterpriseExchange Server 2010 Standard


Consider the following scenario:
  • Some Microsoft Outlook clients connect to a Client Access server array by using a hardware load balancer in a Microsoft Exchange Server 2010 environment.
  • One of the Mailbox servers freezes.
In this scenario, all the threads of the RPC Client Access service (RPCClientAccess.exe) on all Client Access servers in an Active Directory site display a pending status. Eventually, the threads become exhausted. Additionally, users cannot access their mailboxes in their Outlook clients.


This issue occurs because the limit for the number of pending threads in the RPCClientAccess.exe process is not low enough. Therefore, it takes a long time to call back threads from the Mailbox server that freezes.


To resolve this issue, install the following update rollup:
2866475 Description of Update Rollup 2 for Exchange Server 2010 SP3


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

More Information

For more information about the RPC Client Access service, go to the following Microsoft website:For more information about hardware load balancers for Exchange Server 2010, go to the following Microsoft website: