Cumulative Update 13 for Exchange 2019 is now available. With the new release model, it is officially called; The 2023 H1 Cumulative Update (CU) for Exchange Server 2019.
Exchange 2019 CU13 includes the following major changes;
- Enable Modern Auth for pure On-Premises Exchange users
Support for OAuth 2.0 (also known as Modern authentication) for pure on-premises environments that use Active Directory Federated Services (AD FS) as a security token service (STS).
To use this feature, you must be using Microsoft Outlook or any other client that supports Modern authentication by using AD FS. Currently, this feature is available only for Outlook on Windows. However, support for modern authentication will be added to other Outlook clients in the future.
For details see; Enable Modern Auth in Exchange Server on-premises.
- Configuration backup and restore
Setup now backs up the most common configuration settings and then restores them to the state they were in before Setup was started. Starting with the 2023 H1 CU, Setup preserves about 70 different configuration settings across multiple files.
For details see; Exchange Server custom configuration preservation
There are 28 additional fixes documented for this release. A few notable ones are;
- KB5026273: Outlook configuration fails in Android or iOS
- KB5026156: Outlook search fails in a shared On-Premises mailbox if the primary user mailbox is migrated to Exchange Online
- KB5026267: OWA stops responding in an Exchange 2019 and 2016 coexistence topology
- KB5026278: Mailbox migration fails after Extended Protection is enabled
- KB5026138: Users receive reminders although the meeting reminder is set to None
- KB5026139: You can’t move the public folder mailbox
This release does not include new updates to the Active Directory Schema for Exchange 2019.
The next planned Cumulative Update for Exchange 2019 is in September 2023.
Exchange 2019: CU13 KB5020999 – Download
View: Blog post of the Exchange Team about CU13 for Exchange Server 2019
Note: Exchange 2016 has reached its Extended Support phase and CU23 was the last CU for it. This means that from now on, it will only receive Security Updates.