The Windows Cumulative Update installation failed after this procedure.

[yonoff]

I tried to add the Wireless Display feature to a mounted, sysprepped image by following this procedure: (DISM /Image:%MountDir% /Add-Package...).
This process works on the LTSC 2021 OS build 199044.6093 (July 2025 LCU). After deploying the image, the feature works as expected.

However, I'm unable to install the latest Windows Cumulative Update on the image that includes the Wireless Display feature. I tried to install the August 12, 2025, LCU (KB5063709) update using Windows Update and by running the MSU file from the Microsoft Catalog. The update always fails with error code 0x80073701.

To ensure this is the root cause, I created two images of LTSC 2021, one with and one without wireless display; all other configurations are the same.
The update issue only occurs with the image that has wireless display components.

[Solivictus]

You should be able to update Windows after removing the "illegally" added packages, Then you can find the respective esd package for your NEW build version on dump site, repeat the process again.

[bananakid]

@Solivictus, thanks for posting the solution to the problem on Reddit. I fell like it's reasoable to put information from this Reddit comment somewere in the repository too.