Both worked perfectly for a few days but now refuse to find anything.
Fortunately they both still work on my wife's Windows 7 laptop.
Very strange as I have changed nothing.
Didn't you just add MS200 via homeplug?
Assume that wife's laptop is connected via wifi?
Try temporarily connecting the ultrabook via wired and checking that. If that works, then disconnect wired and try wifi again. Hopefully your ultrabook will have cached the core IP and wont then need to discover it again. You will need to connect via wired for Sooloos config though.
I have two wireless access points, one a Thomson router supplied by O2 and another integrated into a home plug connector. Whilst neither allow user configuration of the wifi multicast beacon settings, the O2 router does as far as I can see, no filtering of multicast messages, whilst my homeplug based connector filters about 80% of multicast messages.
To put this in perspective, the Sooloos discovery beacon that I think is used by Control:PC/Mac etc is iirc broadcast approx once every 20 seconds. I think the search for core is slightly longer. On a single pass, Control:xx should receive this discovery beacon however, when multicast is filtered by the wireless access point, then chances of detecting this beacon in a single attempt is far less and you may find that it takes many attempts to discover core.
However, once core is discovered (and its IP isn't subsequently changed), I believe that Control:xx caches the address so the discovery process is not needed unless there is a network glitch and it fails to connect to core. Which is why I believe that I get instant connections with Control:Mac even though, statistically, I would need to restart search for core about 5 times.