I have just bought a pair of TP-Link powerline adapters (TL-PA211) and I'm trying to test speeds around a very large building. When plugging into the sockets that are the furthest away from the other unit the PowerLine LED does not light up, giving the impression that there is no powerline network available (perhaps they sockets are too far away, different circuits etc), however, there is a connection which I can clearly see using the TP-Link utility tool.
So the powerline adapter is working upstairs, but the light isn't coming on. When downstairs the speeds are of course faster, but the light does come on. I don't want to invest any more money getting the entire building fitted with these things if they aren't going to work, but they seem to be working bar the light telling me they aren't!
The manual states that if the powerline LED is not lit, then there is no powerline network detected. But they are connected and working fine, so I'm scratching my head as to whether there is some other problem I need to be aware of before buying some more units.