@KostaNed 

Good day,

Thank you very much for your time and patience.

Sorry for the delay.

Did the powerline light lit up on both adapters?

And is your computer connected by Ethernet cable or Wi-Fi?

Please also check the IP address and default gateway on the computer, such as

Have you tried to turn off the firewall on the computer to have a look?

By the way, are you able to log into the web interface via http://tplinkplc.net?

If yes, what Is the current firmware version on the TL-WPA4220?

Thanks a lot.