Today, Cumulative Update 8 for Exchange Server 2013 was released by the Exchange Team (KB3030080). This update raises Exchange 2013 version number to 15.0.1076.9.

This Cumulative Update introduces changes in the following areas:

• Calendar and Contact Modern Public Folders favorites added in Outlook are now accessible in OWA.
• Batch Migration of Public Folders to 2013 improves migration throughput and PF migration experience.
• Increased support limits for Public Folders with Exchange on-premises deployments (500,000 for co-existence, or 1,000,000 for CU8-only deployments). Number of supported PF mailboxes stands at 100 though, with a per-PF mailbox limit of 100,000 Public Folders.
• Supported EAS clients are now redirected to Office 365 upon successful Hybrid migration.

Next to DST corrections, this Cumulative Update introduces the following fixes:

• 3045301 SMTP is not transported over TLS 1.1 or TLS 1.2 protocol in an Exchange Server 2013 environment
• 3040681 MapiExceptionTimeout error during a hierarchy synchronization process of multiple public folders in Exchange Server 2013
• 3037417 Outlook cannot download an OAB file in an Exchange Server 2013 environment that mixes Exchange Server 2010
• 3037291 Can’t add members to Outlook contact group by using MAPI over HTTP
• 3036952 Mailbox quota warning messages are not sent out after you migrate from Exchange Server 2010 to Exchange Server 2013
• 3036374 Incorrect NDR size limit message is displayed for German localization in an Exchange Server 2013 environment
• 3036365 “The specified address is not recognized or does not exist” error message in an Exchange Server 2013 environment
• 3032153 Recurring events in Calendar over DST are not adjusted on all ActiveSync devices in all Exchange Server environments
• 3031133 Default folders are duplicated after you migrate mailboxes to Exchange Server 2013
• 3031069 Mails are spoofed in Office 365 or in an Exchange Server 2013 environment
• 3030629 Outlook cannot open a shared folder on which a group you attend has the Reviewer permission in Exchange Server 2013
• 3018518 Garbled text in the Japanese “From” field in a forwarded DBCS message
• 3016440 Public folder mailbox quarantined
• 3012266 Update to increase availability address spaces to 200 in Exchange Server 2013
• 3011579 SaveChanges fails and generates a MAPI_E_NOT_FOUND error message on a large message body in Exchange 2013 CU6
• 3006861 “The SMTP address has no mailbox associated with it” error when you access a user’s mailbox by using EWS application
• 3003974 Improved support for MSG files in an Exchange Server 2013 environment where OPENTEXT products are used
• 2988060 Cannot see the auditing results for an HttpModule-based extension for MAPI over HTTP protocol in Exchange Server 2013
• 2986941 “An Active Directory error 0x51 occurred” error when you run the “Setup /PrepareAD” command from a DC in Exchange 2013
• 2961741 Exchange Server 2013 delegated setup fails when the setup account is a member of Domain Admins

Notes:

• When using Exchange hybrid deployments or Exchange Online Archiving (EOA), you are required to stay current.
• Previously released CU7 introduced changes to prevent restoration of pre-CU7 databases. Pre-CU7 users are advised to perform a full backup post-upgrade to CU7 or later.
• Previously released CU7 added support for hierarchies containing 250,000 modern public folders. Consult this article for co-existence scenarios.
• Previously released CU5 introduced OAB architectural changes which are documented here. If you are affected, it is recommended to update CAS servers prior to Mailbox servers.

This Cumulative Update does not include schema or Active Directory changes when compared to Cumulative Update 7. If you have deployed a version earlier than CU7, make sure you run PrepareSchema /PrepareAD.  If you want to speed up the Cumulative Update installation process, you can temporarily disable certificate revocation checking as described here.

Note that Cumulative Updates can be installed directly, i.e. no need to install RTM or Service Packs prior to installing Cumulative Updates. Note that once installed, you can’t uninstall a Cumulative Update nor any of the installed Exchange server roles. The order of upgrading servers is irrelevant, unlike with previous generations of Exchange.

Finally, and I can’t emphasize this enough: For any Hotfix, Rollup, Service Pack or Cumulative Update, I’d recommend to thoroughly test this in a test and acceptance environment first, prior to implementing it in production. When you lack such facilities, hold out a week or two and monitor the comments on the release article or TechNet forum for any issues.

You can download Exchange 2013 Cumulative Update 8 here; UM Language Packs can be found here.