Did you ever figure this out. I'm in the same condition. Prior to installing the driver both the basic and WCID drivers via zadig-2.5.exe, I saw a USB device in the Windows 10 Device Manager, as STM32 Bootloader... but it appeared to have no driver. Not the device appears in the USB Devices root of the Device Manager. In dfusedemo, the dropdown for "Available DFU Devices" is active, but contains no entries.
I've attempted all of the normal things. Reboot, plug and unplug the device. Restart the device. No luck.
According to both the NanoVNA screen and Windows Device Manager, the device is in DFU mode.
Environment: Windows 10 x64, Defuse Demo v3.0.6, NanoVNA H v 3.4
