neowin[.]net/news/windows-10-patch-tuesday-updates-are-now-live-here039s-everything-that039s-fixed/
neowin[.]net/news/windows-7-and-81-patch-tuesday-updates-are-out-here039s-what039s-new-2/
Included in the cumulative update for Win10, Point & Print, which has been the subject of loads of articles by security researchers for making Windows more vulnerable to being hacked, now requires Admin permission. In the notes about possible known issues after updating, Microsoft says that the May or June 2021 update may have broken Windows Update. The fix is to reinstall Win10, and they go on to show a registry entry which should force Win10 to reinstall on its own. Basically the same conclusion I came to when Windows Update broke on 3 or 4 copies of Win10 -- I just mount the latest ISO in Win10 & run setup, rather than wait for Win10 to decide to reinstall at some unknown, and likely inconvenient time.
support.microsoft[.]com/en-us/topic/kb5005322-some-devices-cannot-install-new-updates-after-installing-kb5003214-may-25-2021-and-kb5003690-june-21-2021-66edf7cf-5d3c-401f-bd32-49865343144f