Bug Report: Cumulative Update / Preview Update fails with Error 0x800f0991 on Windows 11 25H2 images

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Provide a clear and concise description of the issue.

Description

When creating a custom Windows 11 25H2 image using microwin injected with the latest official drivers, Windows Update fails to install the May 2026 Preview Update (KB5089573) and Cumulative Update (KB5089549).

The update process hangs for a long time before eventually failing with installation error code 0x800f0991. Standard Windows Update repair techniques (like SFC and DISM) fail to resolve the issue, suggesting that a component stripped or modified by microwin during image creation is breaking the servicing stack dependencies required for this update sequence.

Steps to reproduce the issue.

Steps to Reproduce

1. Generate a custom Windows 11 25H2 image using microwin.
2. Integrate the latest official hardware drivers into the image during the build process.
3. Install the resulting OS on a device or virtual machine.
4. Check for updates via Windows Update and attempt to install KB5089573 / KB5089549.

Paste the full error output (if available).

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Additional context.

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Start by reproducing the Windows 11 25H2 image workflow described: build with microwin and injected official drivers, then attempt KB5089573 and KB5089549. Inspect the image-creation and driver-injection paths for servicing components that are stripped or modified, and collect the failure details. Done means identifying the incompatible change and confirming both updates install successfully on a rebuilt image.