One of our remote Windows 7 Professional users juste reported that he received an Upgrade Reservation Offer for Windows 10. It appears le Get Windows 10 "App" running in his system tray is legit. So far, this is seulement seems to be hitting devices that are pas domain-joined.
Short of uninstalling/hiding le Windows Update that enabled le upgrade, is there tout way to désactivez le Upgrade App (and of course le upgrade itself)?