See the Exchange Team blog here for information:
http://blogs.technet.com/b/exchange/archive/2012/08/14/released-update-rollup-4-for-exchange-2010-service-pack-2.aspx
See the Roll-Up Update page here – http://support.microsoft.com/kb/2706690
Download the Roll-Up Update here:
http://www.microsoft.com/en-us/download/details.aspx?id=30478
Twenty two updates were included in this Roll-Up Update. Quick run down of the updates:
2536846 Email messages sent to a mail-enabled public folder may be queued in a delivery queue on the Hub Transport server.
2632409 Sent item is copied to the Sent Items folder of the wrong mailbox when a user is granted the Send As permission.
2637915 “550 5.7.1” NDR when an email message is sent between tenant organizations in a multi-tenant.
2677727 MRM cannot process retention policies on a cloud-based archive mailbox if the primary mailbox is on-premises.
2685001 Retention policies do not work for the Calendar and Tasks folders.
2686540 Journal report is not delivered to a journaling mailbox.
2689025 Performance issues when you use the light version of Outlook Web App.
2698571 Some email messages are not delivered when you set the MessageRateLimit parameter in a throttling policy.
2698899 Add-ADPermission cmdlet together with a DomainController parameter fails.
2700172 Recipient’s email address is resolved incorrectly to a contact’s email address.
2701162 User A that is granted the Full Access permission to User B’s mailbox cannot see detailed free/busy information for User B.
2701624 ItemSubject field is empty when you run the Search-MailboxAuditLog cmdlet together with the ShowDetails parameter
2702963 The “Open Message In Conflict” button is not available in the conflict notification message.
2707242 The Exchange Information Store service stops responding.
2709014 EdgeTransport.exe process crashes intermittently.
2709935 EdgeTransport.exe process repeatedly crashes.
2713339 Multi-Mailbox Search feature returns incorrect results when you perform a complex discovery search.
2713371 Throttling policy throttles all EWS applications.
2719894 The Microsoft Exchange RPC Client Access service consumes 100 percent of CPU resources and stops responding on a CAS server.
2723383 Incorrect time zone in a notification when the Resource Booking Attendant declines a meeting request from a user in a different time zone.
2724188 A subject that contains colons is truncated in a mixed Exchange Server 2003 and Exchange 2010.
2726897 Event 14035 or Event 1006 is logged when Admin sessions are exhausted.
