From my experience, WU only re-installs CU if another update overwrote its files or metadata. Normally like a SSU or .NET package.
WU wants to restore a handful of files, but downloads the whole package to extract them.
Let's step through this one update at a time.
1. Download 21H2 (19044.1288) with MCT. Remove extra editions: keeping Home, Home (SL) and Pro.
What's the
fewest required updates? KB5011487 (CU) & KB5009467 (.NET)
Why exclude KB5005260 (SSU) and KB5010524 (DU)?
CU includes the latest SSU package (19041.1525), superseding 5260 (19041.1161). DU has nothing to do, since our CU + SSU stack is current.
2. Integrate the bare minimum updates (CU & .NET), across all editions.
View attachment 6899View attachment 6903
Install Home. WU didn't ask to repeat CU.
View attachment 6900
3. Does adding DU make a difference? Not for me.
View attachment 6901
4. I know what you're thinking. We haven't tried SSU, CU, .NET and DU together on a clean .1288 image.
To speed up testing, I only applied this to Home -- skipping SL & Pro.
View attachment 6902
What's the difference in our environments, besides VM platforms? NTLite was self-hosted (in VM) on the same image, to remove any possible influence from my actual host. My advice if you want to debug this, don't repeat testing by applying changes across all editions.
That's a huge waste of time, slowing you down. One install image is enough to work with.
