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 Exchange Server Build Numbers, Cumulative Updates (CU), Security Updates (SU) and Release Dates

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:

  • Exchange Server 2019 CU14 and CU15
  • Exchange Server 2016 CU23

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

Update installation

The following update paths are available:

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.

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.
 

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