On my 2014 Bravia KDL-55W800B smart TV I looked all over for this and then spent 40 minutes on the phone with bewildered Sony support reps. On my TV it turns out the Activate Enhanced Features is not in the XCross Bar then Network options. In addition to that there is no Network icon on the XCross Bar. Network is now a sub icon under the Settings icon.
Activate Advanced Features on my TV is only available through an App. To find the app, named "Activate Enhanced Features", you first have to connect to the internet, update, then refresh the internet connection. Then go to the TV Home page, scroll to All Apps, then look for the Activate Enhanced Features app (among the 80+ apps that are listed). The name will be truncated, so look for an app whose name starts with "Enhanced".
Also, once in that app, select to register the device through the web. That will bring up a page that should show you your Registration Code. If you select to register THROUGH the device you will not see the page with the code.
Hope this helps some others. Was a very frustrating experience as I need the Reg Code to register some other apps.
I moved the Activate Enhanced Features App to My Apps so that I can find it easier should I need to in the future.
Last edited by fppilot; 10-10-2014 at 02:28 PM.