Hotfix update for Microsoft Exchange Server 2019 CU15 HU2 was released on May 29, 2025. It includes fixes for nonsecurity issues and introduces new features. These fixes and features will also be included in later cumulative updates for Exchange Server 2019.
Microsoft has released Hotfix Updates (HUs) that address issues in earlier updates for:
- Exchange Server 2019
- Exchange Server 2016
HUs are available for the following specific versions of Exchange Server:
The May 2025 HUs do not contain any new Exchange Server security updates but contain fixes for non-security issues. Please see the release KB article for more information.
Issues that this hotfix update fixes
- Journal message returns “ConversionFailedException”
- Calendar print doesn’t work in OWA from Exchange 2019 CU14 onwards
- Edge Transport service stops responding after installing November 2024 SU or Exchange 2019 CU15
- StoreWorker fails because of BaseViewOperatorDefinition
Update installation
The following update paths are available:
- Inventory your Exchange Servers to determine which updates are needed using the Exchange Server Health Checker script. Running this script will tell you if any of your Exchange Servers are behind on updates (CUs, SUs, or manual actions).
- Install the latest CU. Use the Exchange Update Wizard to choose your current CU and your target CU to get directions.
- Re-run the Health Checker after you install an update to see if any further actions are needed.
- If you encounter errors during or after installation of Exchange Server, run the SetupAssist script. If something does not work properly after updates, see Repair failed installations of Exchange Cumulative and Security updates. Also please see File version error when you try to install Exchange Server updates.
Get Cumulative Update 15 Hotfix Update 2 for Exchange Server 2019
Microsoft Download Center
You can get the standalone update package through the Microsoft Download Center.
- Microsoft Exchange Server 2019 Cumulative Update 15 HU2 – Download the package now
Get Cumulative Update 23 Hotfix Update 16 for Exchange Server 2016
Microsoft Download Center
You can get the standalone update package through the Microsoft Download Center.
- Microsoft Exchange Server 2016 Cumulative Update 23 HU16 –Download the package now
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