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Yesterday, Microsoft released the latest and likely final major update for Exchange Server 2019. This update includes a range of new features and bug fixes. As always, remember to use the Exchange HealthChecker.
Here direct link for downloading: Exchange 2019 CU15
Let’s start with the list of changes:
- Support for Windows Server 2025
- Feature Flighting in Exchange Server (new features are not enabled by default but are released through rings)
- TLS 1.3 support on Windows Server 2022 (except SMTP, coming later)
- AMSI integration has been improved
- In-place upgrade from Exchange 2019 CU15 to Exchange SE
- Certificate management via EAC (Web GUI) is possible again
- Coexistence with Exchange 2013 is blocked and no longer possible
- Extended Protection is automatically enabled (CAUTION in various scenarios)
Note on Extended Protection: It cannot be enabled during the installation of the CUs, as with CU14. Here are the scenarios where EP is not supported:
Additional information about EP can be found here.
Upgrade scenario Exchange 2019 CU14/15
see also Upgrade path Exchange SE
Upgrade scenario Exchange 2016 CU23
Feature Flighting in Exchange Server
This new feature allows Microsoft to release new functionalities without activating them initially. This is intended to prevent issues and avoid immediately disabling all Exchange Servers. With CU15, this feature is included automatically, and only the ring to be used can be set.
To adjust the ring, PowerShell can be used on the Exchange Server.
Set-ExchangeServer -Identity <ServerName> -RingLevel 0
Functions and status can also be retrieved via PowerShell.
Get-ExchangeServer -Identity <ServerName> | Format-List Features* Get-ExchangeFeature -Status "Enabled"
I wish you the best of luck with the upgrade to the final CU for Exchange Server 2019. If you found the article helpful, please click ‘helpful’.
