I’ve found the issue. So this might help other users in the same situation.
I have to add that this person Georges B. from Steinberg support made me lose 2 precious weeks, even if I told him several times that I had pending exports !!
The problem is obviously an issue with nVidia drivers and the Steinberg USB Licenser. Old dongles like mine (over 8 years old) have to be replaced with a new one.
I did also raise this point with the support several times, but never got any answer than if you think that’s the issue go buy a new one, unbelievable!!!