Some users have used System restore ...
Yes, I know - but presumably only some of those who were having problems. There is evidence that uninstalling KB3004394 either manually or using KB3024777 brings its own crop of problems, like having to re-activate Windows or display drivers that stop working. I asked whether there's any danger in keeping KB3004394 if it's not causing problems. This is not at all clear from any of the documentation I can find.
I'm also concerned about this update - KB3024777 - that seems determined to install itself despite the fact that I don't want it. I've never come across such a persistent Windows update before that won't allow itself to be hidden:
