Microsoft releases Windows Server Preview Build 26212

Windows Server Long-Term Servicing Channel (LTSC) Preview build 26212 is released to Windows Server 2025. It is the same version released to the Canary channel.

This build contains Desktop Experience and Server Core installation options for Datacenter and Standard editions, Annual Channel for Container Host, and Azure Edition (for VM evaluation only).

With this version, the Redmond-based tech giant introduced the Delegated Managed Service Accounts (dMSA) capability. The dMSA account type enables a safe and secure migration from a conventional service account to a machine account with the help of fully randomized keys while disabling account passwords.

Using dMSA can prevent people from stealing passwords using a hacked account, which is quite common with old-style service accounts. If you want to know more about dMSA capability in build 26212, you can read this guide.

The official blog mentioned that if you have signed up for Windows Server Flighting, you should get this new build automatically. If you want to opt in, you must go to Windows Update in the Settings app and Check for updates. You will get a new build as a Feature update, and you are in!

You also get a new Feedback Hub app for Server Desktop users. The app will be updated automatically to the latest version. If not, you can head to the App’s Settings tab and click Check for updates.

Microsoft also mentioned not getting confused after seeing this flight’s label. It may incorrectly reference Windows 11. However, you will see the package installed is a Windows Server update. The Redmond tech giant also assured that this incorrect labeling issue will be fixed in future releases.

Here are other known issues mentioned in the official blog:

Upgrade does not complete: Some users may experience an issue when upgrading where the download process does not progress beyond 0%.  If you encounter this issue, please upgrade to this newer build using the ISO media download option. Download Windows Server Insider Preview (microsoft.com)

VMs created using ISO media may not boot: Some users may encounter boot issues when creating Gen 2 VMs using this build (26063) and attempting to set the DVD ISO as boot preference. The new VM is unable to boot through the ISO and skips to subsequent boot options. This will be addressed in a future release.

Access denied error when using Diskpart –> Clean Image on Winpe.vhdx VMs created using WinPE: Create bootable media | Microsoft Learn. We are working to resolve this issue and expect to have it fixed in the next preview release.

Setup: Some users may experience overlapping rectangle voids following mouse clicks during “OOBE” setup. This is a graphics rendering issue and will not prevent setup from completing. This issue will be addressed in a future release.

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

This is the other information related to the Windows Server Preview Build 26212:

• Windows Server Long-Term Servicing Channel Preview in ISO format in 18 languages, and in VHDX format in English only. 
• Windows Server Datacenter Azure Edition Preview in ISO and VHDX format, English only.
• Microsoft Server Languages and Optional Features Preview

Keys: Keys are valid for preview builds only 

• Server Standard: MFY9F-XBN2F-TYFMP-CCV49-RMYVH
• Datacenter: 2KNJJ-33Y9H-2GXGX-KMQWH-G6H67
• Azure Edition does not accept a key

The official blog also mentioned that this Windows Server Preview will expire on September 15, 2024.

If you are still not part of Windows Insiders for Business, you can sign up today at the official website. The registered insider user can go directly to the  Windows Server Insider Preview download page.

Have you installed Windows Insider’s new build? If so, share your experience with our readers in the comments below.