For the past two mornings, when I have sat down at my computer (Dell Inspiron desktop) I have found a message on the screen that updates failed and it is restarting.
This evening I checked Windows Updates and it said the update to Windows 10 release 21H2 was ready, so I told it to go ahead and install it.
It failed. Download okay, the install was churning along up to around 50%, so I walked away. When I can back, it was undoing whatever it had done.
Why can't I install 21H2?