@Kenta49 According to TP-Link Deco FAQ-2930 this error message happens before user ID and password are verified. It has nothing to do with owner/manager of the network. The app scans network and...

DerekT wrote If I know now what these Decos are and how they connect, I would not have bought them. I was assuming that they were connect wirelessly like my TP-Link range extender does, but would be...

@DerekT Cat5E is not going to be enough to support 2.5 gigabit speeds. To get 2.5 gigabit speed, you need a Cat6 cable. That would explain why you can use this cable with gigabit Ethernet port, but...

@Kenta49 M9 Plus firmware 1.2 is from 2019, soon to be 5 years old. It does not have Web interface. It does not accept firmware update through Deco app. You must update firmware manually to newer...

@cognis0 I am using third-party wall mount holder with one of my M9 Plus, it works just fine for more than 3 years now. It holds M9 Plus tightly in its position.

@moxii Switch Deco mesh to Access Point mode and there will be no settings in it that could impact wired link speed: Switching a Deco to Access Point (AP) Mode Also, just to cover everything, check...