Windows Server build 16257

10.0.16257.1000.rs_prerelease.170728-1630
	Build of Windows Server, version 1803
OS family	Windows 10 (NT 10.0)
Version number	10.0
Build number	16257
Build revision	1000
Architecture	x64
Build lab	rs_prerelease
Compiled on	2017-07-28
Expiration date
Timebomb	2018-07-02 (+339 days)
About dialog

Windows Server build 16257 is the first Insider Preview build of Windows Server, version 1803. It was released on 8 August 2017.

New features and changes[edit | edit source]

Introduced the Remote Server Administration Tools (RSAT) packages as a downloadable package.
The Windows Subsystem for Linux was made available to Windows Server for the first time.
With the assistance of WSL, Windows Server can run node.js, Ruby, Python, Perl and Bash scripts and other tools that are designed for Linux.
The Server Configuration console is now a lighter shade of blue as opposed to the darker one used in build 16237.
Removed the Windows Server 2016 branding from setup and the operating system.

Bisrv.dll (the background tasks infrastructure service) may cause the system to crash with a blue screen of death because of a null class pointer read error (0xC0000005) or a failfast corrupt list entry (0xC0000409) during a DCOM launch. It can also crash if svchost.exe errors out with error code 0xC0000409.
Calling into the firewall service may cause network-using apps to freeze until the system is rebooted. This happens because of an application hang end task error (0xCFFFFFFF) in the Windows firewall API library (FirewallAPI.dll). It occurs when said library is blocked on an advanced local procedure call (ALPC) while it attempts to diagnose a connection failure and retrieve information during network isolation.
Some key functionality to enable end-to-end testing of Cluster Sets scenarios are not present in this build.
You may get a blue screen of death during volume creation and volume repair.