Thanks greatly for all your inputs. I am not prepared to waste more of my and your time on this. Getting into autoruns etc on 10 machines is just not time well spent. I will just look in once a day instead of several times and put up with it.
There seems to absolutely nothing common between my Win 10 machines and my netbook running Win 7 which has completely different installed programs and only a minimum at that but it seems even worse affected with continual refreshes without ever stopping. The strange thing is that it appeared overnight on all the machines around the beginning of August prior to which it was fine.
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