Microsoft has issued workarounds for those users facing issue when upgraded to Windows 10 Insider Preview Build 14267.
Issue of Hyper-V networking connectivity lost on upgrade:
The issue is of those users using Hyper-V and upgrade to the Build 14267 with more than one switch or have multiple virtual networking adapters may lose networking connectivity.
Microsoft has provided two workarounds for this issue:
- Remove all the virtual network adapters connected to the vswitch, delete the vswitch and recreate it, then reconnect their virtual NIC to the new vswitch.
- At admin command prompt, do “netcfg -d” it will wipe-out all the vswitch settings so that you can start from scratch.
So those users upgrading to Windows 10 Insider Preview build 14267 and facing this issue can try these workarounds till the issue gets fixed in future.