KB5005565 Windows 10 2004 19041.1237, 20H2 19042.1237, 21H1 19043.1237 Win Update

ThompsoniusIV said:

I'm right. Even manually windows cant update... :/

So you're back to considering kado897's proposal. If you've never done it before, you'll be surprised at how fast and easy an in-place update is. Just follow the tutorial's guide, and you'll be fine.

Repair Install Windows 10 with an In-place Upgrade | Tutorials:

Repair Install Windows 10 with an In-place Upgrade

To get an ISO? Sure.

I think that if you run the MCTool, everything will fall into place for you.

Downloaded and installed.

Getting it now...

pietcorus2 said:

" You only need to be an insider to get the enablement package offered via Windows Update. "..............so, if you are not an insider , the 21H2-upgrade will not show up in WU............?

Yes, it will not. What will show up is the 5005565 update that takes you to the 1237 index of whatever version you're on (19043, f'r instance).

To move to 21H2 (just for the fun of it, because there's no noticeable benefit, it just looks nice in the window), if you're not an Insider, you have to use the manually applied "enablement package."