Had my new services installed last Thursday but due to covid he couldn’t run cable upstairs. So installed downstairs all good. He said he has activated the 2nd box, today I run a cable upstairs as a temp measure plugged everything in and it all updated and worked but is now giving error 7400. Research says box not activated but the engineer said he had already done this. Any ideas is it a U/S box ?..
Sorry you have misunderstood my router is upstairs so I have connected to the splitter upstairs with a virgin supplied cable and then connected to the box. It just runs across the landing and not through the wall which is what the engineer was going to do. So it is all VM supplied kit just not neat and tidy