@phad Thanks for the photo, very helpful. This box has four Ethernet ports. One is up, that must be one to which Main Deco is connected. Please do the test: connect laptop to one of remaining three...

phad wrote @Alexandre. It's connected directly into the modem @phad But it is modem, not router, right? Can you give me its brand name and model number, just to be sure? Some ISPs mistakenly name...

@phad OK, let's try some other things. Your Main Deco, is it connected to ISP gateway/router or to ISP modem?

@phad You may be able to fix that by logging to Main Deco Web interface. Open Main Deco IP address in browser on device connected to Deco mesh. If you run Deco mesh in Router mode with no changes to...

@Lugari It is not viable. Archer and Deco will not make one WiFi mesh. They will run as independent WiFi routers at best. Put aside Archer router. To provide coverage for dead zones and have WiFi...

@Tay21 Deco E4 has 100Mbps Ethernet ports. If you use E4 as Main Deco, you can't have faster than 100Mbps speeds from E4 no matter what you do. If you want faster WiFi speeds, you will need to...