Purchased this kit less than 4 months ago, have been using TP-Link Powerline extenders for some years. No issue with initial pairing of the units in this kit, the active wifi device was plugged into our conservatory and has been on-line since, until yesterday afternoon. It was moved from one outlet to another and continued working, but moving it back has reset it back to default. Have reconfigured it in an outlet next to its mate, no issue, but when plugged back into its normal location in the conservatory, the mains power LED doesn't even come on, and the network light flashes red, once every 10-15 seconds or so. Simply plugging the device into any outlet inside the house gives completely normal operation, but then putting it back into the conservatory fails as already described.
The line voltage is the same throughout the house, and all wiring connections into and inside the conservatory have been examined for loose wires, etc. (I'm an electrician). There is a smart TV and a DVD/Blu-ray player also in the same room, and they work normally. Can anyone identify what type(s) of conditions would prevent the Powerline adapter from even powering up when plugged in and the outlet turned on, regardless of the state of the network??