@stumpy2384 No problem using a switch, I do just that myself. See attached image of my setup. Just make sure to use a Gbit switch, I had some old switches I used before but I bought a new inexpensive...

@JuanDS This advice is no good in many countries, even if the firmware covers the actual country. When I do what you say in Norway, the upgrade tool and firmware is nowhere to be found. I think it is...

@AlisonC I think that is the way to do it, but see this also: https://www.tp-link.com/us/support/faq/1457/

@AlisonC did you try a factory reset?

@Paramad I don't think it matters what kind of internet connection you have, however the download/upload speed will of course be limited by the external connection. One question to check is if the...

@TP-Link_Deco In my case I have 2 Windows 10 computers and 2 Linux Kubuntu 18.04 computers. What is the suggested system to use to upgrade with?