TP-Link wrote Since not all the network data would go through from Deco, Deco would only get limited information about the clients and the connection alerts might not be fully functional; @TP-Link...

@tahseenomar90 TL-WN781ND Wireless Adapter is quite old. It is possible it does not understand (does not handle well) dual band and/or mesh technologies. I would suggest, as a first step, to again...

@Panayiotis91 This is really bad signal quality. For Satellite Deco M5 to perform well, you should have something like this: Can you clarify: second floor Deco, did you position it just above first...

@VaclavS Ethernet backhaul should work, if you wire Deco units correctly. See this: General questions about Ethernet Backhaul feature on your Deco

@Elbetosan I had once similar error message for Android set-top box connected to one of my not smart TVs. I had to power off/on everything together: Decos (Main M9, Satellite M9, Satellite M5), ISP...

@CD5 1. How about: Old router (WiFi turned off)-> Deco (Router mode) - does it work? If it works, and you are not getting double NAT issues, let it be. If you are getting double NAT issues, you can...