I think you must be right about the Vu+ drivers, twol. I've since tried my Vu+ Solo 4K with another Unicable LNB, a Maclean MCTV-785 DCSS with 16 user bands, and it refused to see this too. So I connected it to my GigaBlue receiver instead, and it worked immediately I began changing the tuner settings. My Inverto SAT>IP box is now running on four of the remaining eight user bands. And I've moved my Vu+ box back to the Spaun SUS 5581 Unicable switch. Thank you again for your advice.