The moment I wrote it my windows got that stuck that it won't return to the desktop after login...just a black sreen with a moving mouse...F*** me right.
Have you tried different USB adapters? "WDF" is probably Windows Driver Framework and QGC does not provide any drivers. I would suggest loading a new driver for the dongle, but the fact that it doesn't work on Mac either would suggest something wrong with the adapter. At any rate, this doesn't sound like a QGC problem per-se.
I solved the driver issue on the mac side by installing a new driver but couldn't access windows since then...I tried several driver installations on windows though but no change