Windows Server Preview Build 26280 is now out but it has dozens of known issues

Microsoft released the Windows Server Preview Build 26280, which contains both the Desktop Experience and Server Core installation options for Datacenter and Standard editions and the Annual Channel for Container Host and Azure Edition.

This new build is labelled as a Windows Server 2025 preview, and if you’re part of the Server Flighting program, you’ll receive it automatically today.

Starting with this release, the Windows Admin Center (WAC) app has been included in the build, making it easier for you to install it on your server. You can download the app from the Windows Server Store, and it is also available as an inbox app on the Windows Server Desktop.

Additionally, build 26280.5000 includes a new Feedback Hub app. The latest version can be obtained by checking the app’s settings tab for updates.

There are a few known issues to be aware of. Sysprep cannot generalize images: This build has a known issue that prevents images from being generalized via Sysprep. The problem is understood and will be fixed in a future release.

The label for this flight may incorrectly reference Windows 11. However, when selected, the package installed is the Windows Server update. This issue will be addressed in a future release.

Applying the WinPE-Powershell optional component does not correctly install Powershell in WinPE. As a result, Powershell cmdlets will fail. Customers who are dependent on Powershell in WinPE should not use this build.

Windows Server 26280 also has an issue where archiving event logs with the “wevtutil al” command causes the Windows Event Log service to crash and the archive operation to fail. The service must be restarted by executing “Start-Service EventLog” from an administrative command line prompt.

Microsoft has published the ISO and VHDX files for Windows Server 2025 preview build 26280.5000 and the Azure Edition. The company has also made available language and optional feature packs.

It’s worth mentioning that Windows Server 26280 is set to expire on September 15, 2025, just a few weeks earlier than the planned EOS of Windows 10 in October 2025.

You can read the full changelog here.