Hotfix update (HU) 2 for Microsoft Exchange Server SE RTM was released on September 8, 2025. It includes fixes for non-security issues and may introduce new features. These fixes and features will also be included in later cumulative updates for Exchange Server SE.
Issues that this hotfix update fixes
Get Hotfix Update for Exchange Server SE RTM HU2
Method 1: Windows Update
This update is available through Windows Update. For more information see Windows Update: FAQ.
Method 2: Microsoft Download Center
You can get the standalone update package through the Microsoft Download Center.
- Microsoft Exchange Server SE RTM HU2 - Download the package now
File information
File hash information
| File name | SHA256 hash |
|---|---|
| ExchangeSE-KB5066373-x64-en.exe | EF95F3AF56046900E01CACB55B6C72AD42F91E536A8212010C0AA7BEDAEF2CE6 |
Hashes for additional languages
The hash tables for additional languages are available here:
- Hash tables for Exchange Server SE RTM HU2 (KB5066373)- Download the hashes now
Exchange Server file information
The English (United States) version of this update installs files that have the attributes that are listed in the following worksheet. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time together with your current daylight-saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.
- Microsoft Exchange Server SE RTM HU2 -Download the worksheet now
More information
For more information about the deployment of Exchange Server SE, see Release notes for Exchange Server SE.
For more information about the coexistence of Exchange Server SE and earlier versions of Exchange Server in the same environment, see Exchange Server SE system requirements.
For more information about other Exchange updates, see Exchange Server Updates: Build numbers and release dates.
Information about protection and security
Protect yourself online: Windows Security support
Learn how we guard against cyber threats: Microsoft Security
References
Learn about the terminology that Microsoft uses to describe software updates.