@sisniper 

The C7 will not be able to be used with the Deco mesh. The OneMesh does not work in conjuction with the Decos mesh, they are seperate.

Only other Decos can be used with other Deco units to join the mesh network.

You can still make it work by moving the topology around.

You can have the Archer C7 connected to your modem, then wire one of the Deco M4s to the Archer C7, set it up normally, then power up the second Deco (don't wire a Ethernet). Finally, setting the Deco as a AP unit so the second Deco can be placed elsewhere in your residence. 

With respect to seemless connection the two Decos will provide that, but once you get near the router you will need to manually connect over or you will see a connection drop while the phone connects to the router and vice versa.

@Tony  thanks Tony , that pretty much what ive done , 2 deco can cover my entire house , so have disabled 2.4 on router , and have hidden the 5ghz for my perosnal use on my work PC , works exceptionally well and 5 bars everywhere , shame its not clear though in the marketing as I would have thought it would work as the deco base unit - also makes perfect sense if it did !

@Tony 

I also have a pair of Deco M4 connected to an Archer C7. Archer is working as my modem/router (I don't have a third device).

My ISP speed is 150mbps, but whenever I try to connect to the Deco, I only get 20 to 40mbps (even cabled!).

Can you please give me some tips so I can get a better speed?

Thanks!

@fGrisi 

Where you place the Decos will affect the speeds, move them closer. If you still have issues please create a new thread.

@fGrisi I found the same at times but in my case I had another AP (unifi AC-lite). Deco and Unifi were on same wifi channel. Once I powered down my Unifi AC-lite, I got full speed. Make sure your C7 and deco's are not on same channel.

@Bercwb 

seems to work fine

have tried disabling wifi altogether on router and this works fine as expected . I've also tried having the wireless hidden on the router - I use this to connect my work devices directly to wifi on router - seems to be ok also 

I do have all my deco's connected via cable though so don't rely on the wifi connecting base stations - mainly as I have too many netflix devices in the house

ium sure you wont be disappointed 

one tip - setup guest in your deco and use that for alexa's etc for improved security - better to do when you first setup than later 

@Bercwb router manages all dhcp