I know, that this works out of the box for Zune-compatible devices, but what about Windows Phone 8? I don't have a micro-SIM yet and there is no way to set up a WiFi hotspot.
By judging what you are trying here to accomplish, I think you are mentioning Reverse USB Tethering. Windows Phone 7 had it by default via Zune. In Windows Phone 8 the dev team dropped this feature. So there is no way you can share your PC's internet to phone via USB.
Most likely what you can do to avail internet in phone, you can set an adapter up as an access point or buy a Wifi router. Then connect your phone to the router via cable or Wifi.
Hope the dev team will give us fully functional USB tether support in WP8.1
As far as I know there is no way to share the comptuers data connection with the phone over USB, you could do it with something Virtual Wifi Wrouter. I've used it and it works very well.
If you have installed the developer preview version of windows 8.1 then it is definitely possible ! Press the bing search on your device then type USB instantaneously there will be drop down menu saying USB settings , press on it and then immediately you will be taken to a screen with two check boxes
- First one " Ask me before using USB DATA connection "
- Second one " Notify me when i connect to a slower charger "
This is a hidden settings found in the preview version and Im hoping it will be there in cyan update too. i haven't tried this out yet but you can have a go and let us know if it works or not