Plugable UGA-3000 not recognized by latest driver. I had this issue the hardware ID was USB\VID_17E9&PID_4324&REV_0121. My fix was I was missing the USB.INF file in the Windows\INF folder on a Windows 7 x64 system. I searched for the file at the root of the windows folder. Copied the file to Windows\INF then updated the drivers on the UGA-3000 object and everything worked.
Thanks for posting! While not directly related to the DisplayLink driver, the behavior you describe can happen from time to time on Windows systems (usually Windows 7, but can happen on Win 8 and 10) where the Windows system file USB.INF is missing or corrupt. You did a great job of isolating the problem and glad you were able to copy over a fresh version of the file from another source to fix the issue.
For the benefit of anyone else following this thread, any time you modify system files there is potential to make things worse and corrupt your system. If one of our adapters or docking stations is not being detected properly after the DisplayLink driver install, please send a PlugDebug file (http://plugable.com/support/plugdebug) to email@example.com so we can examine the contents. This will help us determine if the same fix as used by Dwight is applicable to your case and we can provide specific instructions.
Thanks again to Dwight for sharing his experience!