Update Rollup 12 for Microsoft Exchange Server 2010 Service Pack 3 (SP3) was released on December 15, 2015.
From the Microsoft Exchange Team blog:
This update fixes the issues that are described in the following Microsoft Knowledge Base article:
- KB 3048372 Exchange Calendar items are shifted incorrectly when some Windows DST updates are applied
- KB 3096125 CryptographicException error when Edge Transport service crashes in an Exchange Server 2010 environment
- KB 3097219 Organizer’s name isn’t displayed in the subject of the recurring meeting requests in Exchange Server 2010
- KB 3106421 Very long URLs in an email message don’t open in OWA in Internet Explorer
- KB 3115809 Mailboxes can be accessed when the DefaultNetworkCredentials option is selected when you use Exchange Web Services Managed API to connect to Exchange Server
This update also includes new daylight saving time (DST) updates for Exchange Server 2010 SP3. For more information about DST, go to Daylight Saving Time Help and Support Center.
You have to update in the following order to avoid issues.
1. Client Access Server(CAS). You have to install in Internet-Facing CAS Server first. If you have deployed CAS Array, have to update in each server by disabling connections in Load Balancer(HLB/NLB).
2. Hub Transport Server(HUB)
3. Unified Messaging Server(UM)
4. Mailbox Server(MBX)
5. Edge Server(EDGE)
To download the Update Rollup 12 from the Microsoft, Click Here.