Can you please run

gpg --debug ipc -vK

which will also start gpg-agent and print some diagnostics. You may want to redact the output. You can also run

gpg-agent -v --daemon

which should also print some more info.

Trying to install the update manually (according to windows update my windows is fully updated) it says "This update is not meant for your computer" and aborts.

<3 Microsoft for helpful errors.

In T4427#123774, @werner wrote:

Can you please run

gpg --debug ipc -vK

which will also start gpg-agent and print some diagnostics. You may want to redact the output. You can also run

I'm not currently able to do so (away from that PC for a few days), but will have a closer look next week.

gpg-agent -v --daemon

Starting it manually like this before I removed the update did start the agent, but I was unable to connect to it with gpg - however, I didn't look into that in depth. There was no useful diagnostic output, but I can certainly try again.

As this update lists multiple issues and following fixes for them, maybe it was resolved by Microsoft?

I think we would have gotten more reports about this if this is widespread and I could also not reproduce it on my systems.