I uninstalled the network adapter (device manager), and then scan for hardware changes. After that, restart and wifi is working again (you will have to connect to your networks again).
I use iPhone 6 Plus with Sprint and have unlimited data (no GB caps or monthly/yearly rates). Some months I use over 20GB of data tethering.
You have to root your phone (if Android), or jailbreak (if iOS). But it's easy enough.