Microsoft is Bringing Update Stack Packages to Windows 11

As part of Windows 11 Insider Preview build 22478 in the Dev Channel, Microsoft is starting to test a new way to update the servicing stack in Windows.

What are Update Stack Packages?

Update Stack Packages deliver changes to the Windows 11 update experience before a monthly cumulative update (CU), or yearly feature update, is pushed out to Windows 11 devices. Update Stack Packages shouldn’t be confused with servicing stack updates or feature experience packs.

Microsoft says in a post on the Windows blog announcing the release of Windows 11 Insider Preview build 22478, that “The Update Stack Package will help ensure that your PC has the highest likelihood of successfully installing new updates with the best and least disruptive experience available.”

At this time, the Update Stack Package feature is restricted to updating a small set of update-related system files that Microsoft engineers work on independently from the OS. Microsoft says that by testing this new feature with Windows Insiders first, it hopes to expand the scope and frequency of Update Stack Package releases going forward. Microsoft goes on to detail how Insiders will get Update Stack Packages:

“Update Stack Packages will be delivered to Insiders through Windows Update just like builds and cumulative updates are. Insiders in the Dev Channel today can go to Settings > Windows Update and Check for updates to receive the Update Stack Package.”

Update State Package vs Servicing Stack Update

How Update State Packages differ from servicing stack updates is unclear currently. Microsoft hasn’t revealed much in the way of technical detail in its latest blog post. It could be that Update State Packages are an evolution of servicing stack updates.

Microsoft says that “Servicing stack updates provide fixes to the servicing stack, the component that installs Windows updates. Additionally, it contains the “component-based servicing stack” (CBS), which is a key underlying component for several elements of Windows deployment, such as DISM, SFC, changing Windows features or roles, and repairing components. The CBS is a small component that typically does not have updates released every month.”

Earlier this year, Microsoft started delivering monthly cumulative updates and servicing stack updates together via Windows Server Update Services (WSUS) and the Microsoft Catalog, to provide a single cumulative update payload. Prior to February 2021, servicing updates were supposed to be installed separately before subsequent cumulative or feature updates could be applied.

Windows Feature Experience Packs

Another type of update that Microsoft has been testing with Insiders, and which I expect Microsoft to use more in Windows 11, is the feature experience pack. These packs are designed to add features to Windows independently of a feature update.

Because Windows 11 has shipped with quite a few Windows 10 power user features missing, Microsoft could opt to use feature experience packs to deliver those features in Windows 11. That would mean users don’t need to wait a year for the first Windows 11 feature update. But it remains to be seen whether features like Jump Lists, and the ability to group apps on the Start menu, will be added to Windows 11.