Our wireless is through a B.T. Hub 3 router. Message is - You are seeing this page because you are are using a BT service which requires the use of BT DNS servers and it appears you are attempting to connect using a DNS server outside our network.
Operating system is Fire OS 188.8.131.52 installed Sept 2016.
I am so fed up of not being able get into the forum (SINCE YESTERDAY) on my Kindle Fire HDX7 that I resurrected my old tablet (a Nexus 7 from 2012) and it is behaving like a proper gentleman so I will go back to using that meantime:)
Sorry I thought I had found something. There are lots of complaints/queries about the exact same fault that you are having. Does the Nexus 7 use the Amazon DNS servers. It appears that is where the problem lays. Which ever DNS server is giving out the ip address for proboards is giving an old ip address out. The BT router should be OK. I use a BT router albeit a version 4 but I have no problem with it.
The Nexus (a Google product) has no connection with Amazon at all which is why I have reverted to using it.
A few minutes ago (after long searches, etc) I managed to stumble on a long thread on a BT forum which is the exact thing I was describing ! It is a problem with the Silk Browser and Amazon know about it and are apparently lagging in sorting it out properly. Temporary fixes are around but only last a day or so. I will try and find the thread again and post it here, if that is in order, in case it is useful to someone else. Back shortly