@saltis99 If you open Update Deco page in your Deco app, you will see current Deco firmware there. What firmware version do you see there? In example below Deco M9 Plus runs on firmware 1.6.2:

JouJek wrote All works fine on 192.168.68.xx, 192.168.100.xxx --- in my case only subnts from 192.168.0.1 to 192.168.3.255 are affected -> rest looks fine. I already contacted the TP Link support but...

mariocaz wrote Only to confirm... Can I connect the 2nd Powerline device to any of the Decos I have connected by ethernet, right ? @mariocaz Yes, you can do that.

@Alpaslan One more thing: for Speed Test to appear in Deco app you only need Main Deco to support it. If one of your Deco units supports Speed Test, promote it to Main Deco and you'll have that...

@RobAC It is still OK to use the Ethernet ports on the original modem in non bridge mode, but they will only work without issues for devices which connect to Internet only. For example, Roku or...

@Alpaslan This forum post from TP-Link Support will explain: The models that support "Test Internet Speed"