@GregT Disable 5GHz on Guest network. Password protect it. Connect IOT devices to Guest network. Also, optionally: Disable 2.4GHz on Main network. That is my Deco network setup. Works for me.

@Zazzn1 If the problem comes again, find "DHCP Lease Time" (or equivalent) setting in your router and check what it is set to. If it is set to "Forever" or very long period (weeks), change it to...

@Wobbo Agreed, that could have been done better. Check this forum conversation.

Wobbo wrote A router never establishes and should never check the internet connection itself. @Wobbo Belkin N-series WiFi routers do check the Internet connection, for example. I used to own Belkin...

@TheCommunicator It is client that decides which mesh node to connect to. In your case, that would be "desktop machine." It sees three mesh nodes and by logic which is not under Deco control chooses...

@JBa75 Check this forum conversation: Placement of Deco M9 plus, vertical or horizontal does it matter?