How to Disable Cortana in Windows 10’s Anniversary Update
http://www.howtogeek.com/265027/how-to-disable-cortana-in-windows-10/
….you can still disable Cortana via a registry hack or group policy setting. This transforms the Cortana box into a “Search Windows” tool for local application and file searches.
Cortana has become increasingly restrictive since Windows 10’s release. It was previously updated to ignore your default web browser. Cortana now always launches the Microsoft Edge browser and only uses Bing when you search. If that sounds like something you wouldn’t want to use, here’s how to turn it off.