Please see the screen shot
Hi,
Sorry for your situation.
Which version of D5 Render are you using now?
Does this happen in all scenes? Can you open a Demo Scene of D5 or an empty scene? Please have a try.
And, please also try to right click D5, open it ‘Run as administrator’.
Besides, please try to turn off ‘Settings-Display-Graphics settings-Hardware-accelerated GPU scheduling’ if it is on.