ok guys found the exact issue. Similar to Presonus Studio One 3 requiring KB2670838 windows update… try installing this package from this link: https://www.microsoft.com/en-us/download/details.aspx?id=36805
make sure to reboot. then you should be able to launch Cubase. I am guessing this is now required… Steinberg should say something. I’ve avoided this particular update for years because GUI is a tiny bit snappier without it… but I’ll try the new cubase and see if I like. Good luck fellows.