Nighthawk X6 (EX7700) cannot extend AX1800 (EAX20-100AUS) network

A couple things. 

1. daisy chaining extenders is a poor choice. Especially mesh extenders as there's nothing telling them to connect to the router or to a different extender and it can create instabilities. 

2. I'd go router---ex7700-----eax20.  Reason why is a standard dual band extender looses 50% throughput speed because it has to uses the same wireless chip to go router---extender and then extender----device. And it can't do both at once. The tribands use one of the 5ghz bands just for router----extender communication so they don't take that same 50% speed hit. And they have lower latency. 

That 50% speed hit, the increased latency, and the decreased stability because the extenders don't know which signal to connect to (router or other extender) is usually why we don't recommend daisy chaining them. Especially in extender mode. 

If you're going to do so, follow this. 

1. setup the ex7700 to the router. During setup, uncheck the "extend 2.4ghz" signal button. You'll still be able to use 2.4ghz but it won't use it as failover. It'll rely entirely on the 5ghz backhaul

2. if the extenders are to close to each other and the router, thats where the connection issues come it. When they're setup in a mesh, they just connect to the ssid they're told to connect to. And if the ssid is the same (mesh), it doesn't know if it should be connecting to the router or t he extender. So make sure to have them much further away. If you have to set them up in daisy chained mode and using the same ssid (mesh), you'll want the 2nd extender far enough away from the router that it can't see it. It should only be able to pickup the first extenders ssid

3. I'd highly recommend setting them up in a star topology configuration. And the extenders far enough away from each other that they can only see the routers ssid and not each others. 

4. if none of that works, then disable the mesh and use the ex7700 with its own ssid with it in the middle of the chain. You can go router----ex7700----eax20  that way the eax20 KNOWS it has to connect to the ex7700 because its ssid is unique. 

We don't recommend daisy chaining extenders and I usually don't recommend using 2 extenders at all. If someones needing more than 1 extender, I usually advise them to moving to a mesh system so there's something controlling the system and connections. And if they're needing daisy chained, I'd highly recommend the triband mesh systems.