3/23 Update: AD Schema changes are not made if already running 2013 CU7
3/19 Update: Added info on Public Folder scalability improvements

Exchange 2013 CU8, 2010 SP3 CU9, and 2007 SP3 UR16 were released on 3/17/2015

2013 CU8 | Download | KB3030080 | EHLO Post
2010 SP3 UR9 | Download | KB3030085| EHLO Post
2007 SP3 UR16 | Download | KB3030086| EHLO Post
Some of the above KBs may not be available yet, but should be within 24 hours

Key changes in 2013 CU8

1. Public Folders
   1. Scalability improvements
      1. Up to 1 million Public Folders on 2013, a 400% increase from CU7!
         • Still limited to 100 PF Mailboxes and 100,000 Folders per PF Mailbox
      2. Up to 500,000 legacy (2007 or 2010) Public Folders being migrated to 2013
   2. Support for accessing Calendar & Contacts folders in OWA
   3. Adding favorite folders in Outlook
   4. Improved throughput and migration experience to 2013
      • Throughput is increased via multiple moves being carried at once, one per target Public Folder mailbox
2. ActiveSync redirection to Office 365, after mailboxes are moved from on-premises to O365
   • Both Exchange 2013 CU8 and 2010 SP3 UR9 include this support
3. Updates to AD schema
   • Only if running 2013 CU6 or earlier, CU7 & CU8 have the same schema updates

Also see Tony Redmond’s post on this “boring” update: Exchange 2013 CU8 appears. Instant boredom ensues – but for the best possible reason which is a good thing 🙂

Exchange 2010 & 2103 ActiveSync with hybrid deployments improvements

With Exchange 2013 Cumulative Update 8 and Exchange 2010 SP3 RU9, improvements have been made to Exchange ActiveSync in a hybrid deployment with Office 365. Previously, when a mailbox was moved from an on-premises Exchange server to Office 365, the user’s mobile device would stop syncing with their mailbox. To resolve this issue, the user would need to reconfigure it, to point to m.outlook.com, or recreate the email account on their device.  With the release of Exchange 2013 CU8 and Exchange 2010 SP3 RU9, Exchange will now automatically redirect the mobile device, if it supports this, to Office 365 when the mailbox is moved. With only a few exceptions, the user no longer needs to manually set up their device for mail to keep working. In addition to Exchange 2013 CU8, automatic redirection is supported in the following scenarios:

• Exchange 2007 on-premises organizations (not supported)
• Exchange 2010 on-premises organizations where the following is true:
  • All Exchange 2010 Client Access servers are running at least Exchange 2010 SP3 UR9
  • A hybrid deployment was configured using the Exchange Hybrid Configuration wizard
• Mix Exchange 2010 and Exchange 2013 on-premises organizations where the following is true:
  • A hybrid deployment was configured using the Exchange Hybrid Configuration wizard
  • All Client Access servers have been replaced with either Exchange 2013 CU8 Client Access servers (with at least one Exchange 2013 CU8 Mailbox server) or Exchange 2010 SP3 UR9 Client Access servers

If your organization meets the requirements listed above, mobile devices should automatically be redirected to Office 365 when a user’s mailbox is moved, without any additional configuration. For the best experience, make sure your users’ mobile devices are running the latest versions of their operating systems and e-mail clients. Some mobile devices, such as those running the Android operating system, might not correctly interpret the Exchange ActiveSync 451 redirection instructions sent by Exchange. For these devices, users will still need to manually reconfigure or recreate their email account on the device. If you have questions about whether a device supports Exchange ActiveSync 451 redirection, contact the device manufacturer.

Changes coming in CU9, that were initially on the list for CU8

OWA logoff behavior will change in CU9, see this EHLO article for more details: OWA Forms Based Auth Logoff Changes in Exchange 2013 Cumulative Update 9. This does affect clients using TMG, so read this article to be prepared for the changes coming in CU9.

Also coming in CU9, is the ability to have Sent Items from a shared mailbox to got the shared mailbox Sent Items folder vs. the sending user’s. See this EHLO article for more details: Want more control over Sent Items when using shared mailboxes?

Exchange 2007 SP3 UR16 only change is an update to time zones.

Known Issues

If major issues come up with these updates I will add a section on Known issues later. For Known Issues and updates in 2013 CU7 see: Exchange 2013 CU7, 2010 SP3 UR8, 2007 SP3 UR15 released & Known Issues