I crashed many Win 10 versions trying to turn off bunch of telemetrics and cortana and store and other calling home services by tweaking registry and never quite succeed. Until I find Henry++ Simplewall. Brilliant tool - instead of tweaking regs etc you just shut down access to internet to bunch of services. And boy there is hundred of them trying non stop. So while your windows 10 works fine, cortana, store, telemetry and windows updates believe you have no internet at all.