Just got a new Surface Book 2, and the Ethernet portion of the UD-3900 only shows up as not connected.
All up to date - drivers up to date - hardware is detected, with driver version 8.4.2815.0. Device description shows up as DisplayLink network Adapter NCM.
Previous laptop running the same image of Windows 10 show it still working just fine - but that was a Dell -
The drivers were installed post imaging, updating, and so on. I did try the cleaner utility for reinstalling based on 1+ year old posts to no avail.
If I understand correctly, the same dock in all aspects is working fine on another machine? if so, is this with the same Ethernet cable and connected to the same router?