Resolve 17.1.1 Studio does not render 4k videos with NVIDIA

I'm trying to render a video in 4K UHD with NVIDIA ENCODER and get an error message that the codec cannot be found ... In version 17.1 this still worked fine with the same settings! Graphics card driver is up to date.
The same video with the same codec only in 2k7 is rendered error-free.

Addendum: I just successfully rendered the same video again in 4K H265 with NVIDIA encoder - which caused an error yesterday. Difference: The PC was restarted in between ...
And then another undesirable behavior: every time after the installation of DaVinici or the update, the English keyboard layout is automatically set!