Hello Don!
Please download driver for NanoVNA here
This driver from program DfuSeDemo 3.0.6 for Win7, Win8. Windows 8.1 and Win10. I use this driver for NanoVNA-H, NanoVNA-H4 and TinySA 2.8. Setup program from DfuSeDemo install this driver not automatically.?
DfuSeDemo, NanoVNA-APP, TinySA-APP use this driver for work and FW update.
73 de Vladimir, dl7pga