Simplified deployment of Windows servicing stack updates: what's new
Published Aug 10 2021 10:46 AM 19K Views

We learn a tremendous amount from your feedback and I'm excited to announce that we are now extending combined cumulative update capabilities to more versions of Windows!

Servicing stack updates (SSUs) provide fixes to the servicing stack, the component that installs Windows updates. Last September, we announced that we were working to simplify the on-premises deployment of servicing stack updates. We shared a plan to ease the efforts of IT administrators by providing a single monthly update containing both the latest cumulative update (LCU) fixes as well as the latest SSU, if applicable. This single update package can be installed on a device to ensure that updates are applied in the correct order, thus reducing the chances of installation failures.

Based on learnings from your comments and suggestions, we are improving this capability. Let's take a closer look!

Expanding capabilities to more versions of Windows

We are thrilled to announce that combined cumulative update deployment capabilities are coming to Windows 10, version 1809, Windows Server 2019, and Windows 10, version 1909. Beginning today, you can leverage the Windows Insider Pre-release Category in Windows Server Update Services (WSUS) to deploy the August 2021 monthly quality update and SSU together as a single package to devices running these versions.

More detailed instructions on how to leverage the Windows Insider Pre-release update to deploy these combined packages can be found in our previous post. Deploy Windows SSUs and LCUs together with one cumulative update.

Note: Devices running Windows 10, version 1809 will first need the July 20, 2021 Servicing Stack Update (KB5004424) or later in order to leverage this new capability. Devices running Windows 10, version 1909 will first need the June 15, 2021 Servicing Stack Update (KB5003974) or later.

Dependencies on SSUs and rare exceptions

When we released the first combined Windows cumulative update package, we simultaneously introduced a prerequisite on the September 2020, or later, SSU. This SSU contained the changes that were needed to make devices compatible with the combined cumulative update package, enabling the servicing stack to:

  • Expand the contents of this package.
  • Orchestrate the install of a new SSU.
  • Proceed with installing an LCU using the updated version of servicing stack.

Normally, updates to the servicing stack improve reliability or address a vulnerability in the update process for the LCU, and they are effective immediately for the installation of the LCU packaged inside the combined update package type that carries the SSU. In rare cases, especially as we enhance this capability, there can be breaking changes in the interface between the servicing stack and the combined update package format. In these circumstances, an SSU that makes the servicing stack compatible with the new interface must be deployed prior to the combined (LCU + SSU) update.

Such a change occurred with the May 11, 2021 SSU which is included in the May 2021 Windows 10 monthly quality update (KB5003173) for Windows 10. Here we enhanced bootstrapping capability of servicing stack for offline servicing of the OS image. This introduced a dependency on a new interface, hence the June 2021 monthly quality update (KB5003637) included a prerequisite. While this had little to no impact on most organizations who regularly leverage monthly updates, or any impact on those who connect their devices directly to Windows Update, some organizations were negatively affected by this prerequisite. Therefore, today we are releasing a standalone SSU (KB5005260) that can be applied to Windows 10 devices that have not yet installed the May 2021 monthly quality update.

Going forward, we will strive to minimize any changes that require an SSU as a prerequisite, but if such a change occurs, we will make a standalone SSU available in addition to the combined monthly update to ensure easy manageability.

Please continue to share your thoughts

Thank you for your continued enthusiasm and feedback on making our improved servicing capabilities the best they can be. For the latest updates on new releases, tools, and resources, stay tuned to this blog and follow us @MSWindowsITPro and @ariaupdated on Twitter, or visit the Windows Tech Community for more information.


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‎Aug 11 2021 08:38 AM
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