@yves_b thank you - The server is wired by cat6 to the base Deco unit. The other computers are connected by wifi to the Deco system. They are not on the guest or IoT networks. To check open Internet...

I have a XE75 Deco system. I've run the interference optimizer, on the latest firmware, they are all on the same (primary/non-guest, non-IoT) network, and have set my four test devices to have "high...