Thanks Saab, not a command I had come across before.
Just a thought, if the broadband is being "sent" along power cables from the main house to the cottage, would the signal be able to get through the cottage consumer unit with whatever circuit breaker technology is installed?
The instructions for the powerline type network adaptors I've seen usually state that the adaptors should be plugged directly into a wall socket (not, for example, into an extension lead), so I imagine there might be an issue with equipment "in line" doing something bad to the broadband.
I've never used this sort of adaptor, incidentally.