Microsoft Surface / Window RT missing Bluetooth DUN support

• No Bluetooth DUN (Dial Up Networking)
• BthModem is not supported by the Microsoft Bluetooth Stack
• This means standard Bluetooth Dial Up Networking is not available
• If you have a mobile phone, you must use a USB or WiFi tether unless PDAnet, FoxFI, Tether.com, or similar partner develops a custom driver specifically for these devices