@David-TP any ideas about next steps, David?

@David-TP See if I understood you correctly. I unplugged every Deco that was connecte wirelessly. So only ethernet-connections remained. After that, the Guest-network seems to work fine. I tried 3...

@David-TP any ideas? Thanks!

@David-TP Hi David, thanks for stepping in! The model-number of the switch is in my original post. Hope you can help me! Thanks Tom

Hello, I have a network of 2 pieces M9 Plus and 3 pieces M5. Most are connected wired, some through WiFi. A few weeks ago I have introduced an unmanaged switch in the network, the TP-link TL-SG105....

@cptwonton I was able to update both units. Not completely sure why it worked... But it worked, and I now have the functionality back I was looking for. Now let's hope TP-Link will resume regular...