I got the Windows calls too, told me that unless I upgraded to the latest Windows within 48 hours my Microsoft would be cut off. I have caller ID so I don't answer any # I don't recognize. Also, I already have Windows 10. One day they called me every 30 minutes. I tried blocking the # but my call blocking is now full. Anyway, they just use a different # the next time they call. My Microsoft never got cut off and I haven't gotten any more calls in several days.