Crash on loading game

I now get a crash where all video is lost on entering the menu or entering the campaign.The only recovery is hard power-off. In event viewer I see Error 4101 “Display driver nvlddmkm stopped responding and has successfully recovered.”. its seems its when the GFX is being set up or mode being changed.

GPU is Nvidia 1080Ti

In event viewer I also see a very large group of Error 51 entries around the crash concerning a disk error for a drive number that doesnt physically exist - I understand UWP games involve the use of VDS virtual disks.

When starting the game I see my options are reverted to defaults (e.g. video settings) and all need to be re-done.

Was OK for a while after a reboot, played a chapter then crashed when going back to menu

I cant play the game like this - having to hard power cycle the PC is no good.