Using Vegas Movie Studio 17 Platinum graphics card drivers are fully up to date. NVIDIA GeForce RTX 3060 Ti Drivers updated to 591.74
Error message reads 0x80660008 (no message)
Try going back to an earlier NVIDIA driver. https://www.vegascreativesoftware.info/us/forum/nvenc-nv-encoder-problem-with-new-nvidia-drivers-vp22--150573/
I've just checked with my VMSP17 and Nvidia driver 591.44. Same message
You probably need to go back to driver 581.42. I'm not bothered as I prefer to use Sony AVC instead of Magix AVC, and with that I use my Intel integrated GPU. Not as fast but I don't have any problems whereas Magix AVC with NVE has given me occasional glitches.
I've only in the last one hour downgraded from 591.74 to 581.57 this being the last Studio driver before the dreaded 591 series (44 and 74). I notice that the last Game driver before 591.xx was 581.80 - and there was also a 581.57 Game driver as well.
Link to NVIDIA GeForce drivers: https://www.nvidia.com/en-gb/geforce/drivers/
After opening, hit the Start Search button and the drivers released from September 2025 will display.