I have a similar problem like mentioned in this question:
Unable to create the virtual machine
But, my problem is a bit different in the error description:>
If this problem happens on Windows 10, there's an easy fix... navigate to:
This cleans up all of the virtual network adapters so they can be recreated by the emulator. Once you reboot, delete the emulator and then recreate it and it should create the necessary network adapters in such a way that it will work.
DISCLAIMER: This technique worked for me using Visual Studio Emulator for Android on a Windows 10 machine. I understand it's not Windows 8 and it's not a Windows Phone emulator, but the underlying issue is the same so if anyone lands here and has Windows 10, you may want to try this.