Question about Devolo dLAN 1200+ Starter Kit

Whether Powerline works or not is a bit like winning the lottery, if you are lucky it works without problems, if not then it was just bad luck. I think the product will be taken back if it doesn't work.
At my house, it goes from the kitchen on the second floor, via 2-3 loop sockets, to the sub-distributor on the second floor, from there to the main distributor, via the second floor meter, to the uncountable number of sockets on the second floor.From there to the main distributor, via the second floor meter, to the uncounted socket, to the meter of the ground floor, to the UV ground floor again via 2-3 loop sockets over ancient cloth wires to the socket at which I then installed the second box, so to speak the 6s won in the lottery ;)
But it also depends on what else is connected to the mains that could potentially cause interference, so that the signal cannot be cleanly overlaid and it then doesn't work.
In short: Buy it, try it, if it works you're lucky, if it doesn't you're out of luck&return it.

If it is on the same mains, then it works perfectly, but if the basement is on a different meter (or different phase??), then it does not work. The power cables must be physically connected to each other. To test it, maybe borrow a device from a colleague, it could also be an old one...

Buy

Buy, that runs without problems