Jesse
Change the PID when you test to ensure that Win 10 make a new installation (and doesn't think that it is a VCOM that it has already registered before on that VID/PID).
Also, beware that automatic VCOM installation in Win 10 doesn't seem to work with VNIC - it thinks it is a VCOM and installs it as such, even if it should be VNIC (based on VCOM). Therefore make sure that in the returned configuration descriptor the "device class communication and control" fields are set to 2:0:0 (meaning install manually) and not 2:2:0 (which tells Win 10 to install VCOM automatically).
Regards
Mark
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