My wife's 'phone displayed the "Your connection is not private" message this afternoon when she tried to access the internet, with 'https' in red and crossed through. Both her 'phone and mine are the same Motorola G 4G 1st generation, set up identically so far as I am aware, using Chrome as the browser and DuckDuckGo as the search engine. We share the same ISP and router. NET::ERR_CERT_COMMON_NAME_INVALID is displayed. 'ADVANCED' displays a message, "This server could not prove that it is www.google.co.uk; its security certificate is from www.btwifi.com. This may be caused by a misconfiguration or an attacker intercepting your connection." "PROCEED TO WWW.GOOGLE.CO.UK (UNSAFE)" has no effect when tapped. My 'phone continues to operate perfectly well.
SOLVED: I discovered BTWifi_with_Fon in Settings>Wi-Fi was connected instead of my broadband provider. It is impossible to know how this could have happened because my wife would never go there on her 'phone.
Edited by lithoartist, 01 January 2018 - 01:16 PM.