@jakke91 The soluion concerning the faling update software was disabling all network cards execpt (in my case) the wifi adapter.

@David-TP Thank you for the update. Unfortunately I cannot update the Deco that way, I get:

Problem is with all my pc's/tablets.

Parent control is not working at all. Let's take instagram as an example. I blocked it via the given list and I added it manully. I see it as blocked in history (see picture) but on the device I can...