Problem solved. What is needed actually is to "add" the second adapter through which you create a network. I was trying to "modify" the adaptor I was directly connected to, by inputing its password...

Region : Greece Model : TL-PA211KIT Hardware Version : Not Clear Firmware Version : ISP : I have purchased the PA211KIT AV200 Nano 200Mbps Powerline Adapter - Twin Pack. It was very easy to set these...