Please help... I can't see my TL-PA4010 but I am connected to the internet and wifi and power (all three lights green). 

I have tried looking online to find any help or pages but I'm struggling. I've also tried going into the TP-Link utility-device-thingy (turquoise screen) to see if I can change anything so that I can see the units' names.

Background

This system was working perfectly until about a week ago when I started to have issues with a slow internet connection. This was sorted and my wifi router was working again, although slightly slower than before. 

My wifi router is downstairs and I am trying to use the Powerline Adapters to reach my office upstairs. I live in a cottage and there is a black spot. The kit had managed to overcome the black spot and was working fine and I could see the names of the adapters if I wanted to connect to them. (My laptop uses a combination of plugged ethernet and wifi. If I can't connect to the adapters, I can only connect to a VERY weak wifi router signal which is intermittent.)

Any help will be most appreciated