Sorry MJ5282, but as I said, I'm rather clueless with network stuff. My desktop is configured to obtain IP and DNS addresses automatically. The Sooloos configure program shows both our MC200 and ControlPC in its list of "Devices on network" each with an IP address after "@ alphanumeric_string/ " The two addresses are the same apart from the final value, .45 for the MC200, .47 for ControlPC. The web utility can see the MC200 when I enter its IP address into my browser. When I try to run ControlPC now, I just get that error message as above.
All was fine until we disconnected from the desktop yesterday and played with the MC200 in stand alone mode connected to our audio system. What changed?


Main: 861v8, 818v3, 8000XE, 7200HCUSE, 7200.2, Roon Nucleus+, Shunyata Everest w/ Sigma XC and Alpha NR's, HD621, Oppo 103D, Panasonic P60ZT60 plasma. RJ45 switch on master SpeakerLink lines to select 861 or 818, Etherregen & ENO AG feeding the 818, M-Links.
Room #2: 5200.2s from M218.