Windows Server, version 1709

Windows Server, version 1709
	Version of Microsoft Windows
OS family	Windows 10 (NT 10.0)
Version	1709
Codename	Redstone 3
Architecture	x64
Latest build	10.0.16299.15 (rs3_release)
Release date	2017-10-17
Support end	2019-04-09
Client counterpart
	Windows 10 Fall Creators Update
Replaces
	Windows Server 2016
Replaced by
	Windows Server, version 1803

Windows Server, version 1709 is the first Semi-Annual Channel release of the Windows Server operating system family, released on 17 October 2017. It introduces the then-newly-established Semi-Annual Channel (SAC), intended to support containerized workloads and micro-service applications while retaining a frequent, periodic servicing release schedule for every half-year. Unlike Long-Term Servicing Channel (LTSC) releases, SAC releases are only available in the form of a Server Core installation type, and cannot be upgraded to from an existing LTSC release, such as Windows Server 2016.

Semi-Annual Channel releases typically came with 18 months of mainstream support, and were commercially distributed to volume-licensed customers via the Microsoft Software Assurance program and on the Microsoft Azure marketplace. Developers were also able to obtain a Windows Server SAC release for development and testing purposes through an applicable Visual Studio subscription.

The Semi-Annual Channel was deprecated as part of Windows Server 2022's release; it was superseded by the newer Annual Channel (AC) introduced as part of Windows Server, version 23H2, which had similar if not identical goals to SAC releases.