Windows Server 26257 introduces Server Flighting, allowing users to get preview builds weeks ahead of release

Microsoft released the Windows Server 2025 Preview Build 26257, which offers complete and Azure-only versions for Long-Term Servicing Channel (LTSC) customers. The Redmond-based tech giant introduced many features with it, including setting up the Windows Admin Center management tool directly from the server’s desktop.

The support for delegated Managed Service Accounts (ADMSA) was another introduction to Windows Server. It offers an advanced substitute for Group Managed Service Accounts (gMSA) and is explicitly designed to counter “kerberoasting” attacks on service accounts by binding the account with particular machine identities.

Preview Build 26257 also introduces the Windows Server Flighting. It will allow users to obtain preview builds automatically at some point later on. Also, a Feedback Hub app for Windows Server Desktop users and a new Windows Subsystem for Linux version are part of this.

Certainly, being a preview build, there are a few things to note, such as a bug that halts the upgrade process completely and an issue with using the Diskpart command on some VMs. The full release notes contain a complete list of all known issues and other essential details about this build.

If you are a Windows Server Insider, you can get this build from Windows Update.

In other news, the Windows Insider Program received two new patches: one for the Dev Channel and the other for the Beta Channel. Each brings huge changes to the operating system.