Monthly Archives: September 2012

Fix Windows 8 and Hyper-V Virtual Switch Problems

Wow, that hurts!

One reason I decided to jump onto the Windows 8 bandwagon was that I finally had access to a native VM environment that supports 64 bit operating systems.  Unfortunately, though, I’ve just burnt a couple of hours trying to figure out how to get Hyper-V and Windows 8 to play nicely with one another at a networking level.

My problem presented itself as loss of IP network connectivity which meant my host didn’t have any form of network access.

A quick look around online suggests a few people have had problems as well that sound way, way worse than mine (re-install the host OS, really?!)

The Solution(s)

This may not work for everyone… I’m running a Lenovo T420s that has the out-of-the-box Windows 8 drivers for all its components as Lenovo haven’t moved past beta with their drivers as yet.

Network adapters are: wired: Intel 82579LM Gigabit; wireless: Lenovo 11b/g/n Wireless LAN PCI Express.

I have this approach working for the wired and wireless connections in my machine – the fix is slightly different for each connection type, so here they are.


1. Create Your virtual switch and change no defaults (apart from the Name if you like).  This is how it looks:

How your wired Virtual Switch should look.

After you apply this your underlying physical connection will cease working.

2. Open up Control Panel > Network and Internet > Network Connections.

You will find that you now have “Ethernet” and “vEthernet (Your Switch Name)” connections.

3. Right click on “Ethernet” and click “Properties”.  Under the Networking Tab select all items in the “This connection uses the following items” and then click “OK”.

Windows will now give you a nice warning about items being disabled (such as IPv4, etc).  Click “Yes” on this dialog.

At this point you will see the “vEthernet” connection suddenly switch to “Identifying…..” and a few moments later you’ll be connected to your network (if you’re on a Windows domain the domain name will show).


This process is slightly different as using a Wireless connection creates a Network Bridge as part of the process of setting up a Virtual Switch.

Do the above steps but select your wireless network connection instead this time.

When you are finished you will see two new items in your Network Connections: “vEthernet (Your Wireless Switch Name)” and “Network Bridge”.

Right click on the “Network Bridge” and click “Properties”. Under the Networking Tab select all items in the “This connection uses the following items” and then click “OK”.

Windows will now give you a nice warning about items being disabled (such as IPv4, etc).  Click “Yes” on this dialog.

As with the Wired connection above you should now see your “vEthernet” (wireless) connection switch to “Identifying…” followed shortly by a working network connection.

That’s it – simple – no reinstalling or driver updates are any other shenaningans.

Enjoy your Windows 8 – x64 Hyper V environment!

BTW – you shouldn’t need to jump through all these hoops to get this working and I’m not sure why these problems happen – I was very close to switching back to VirtualBox but thought I’d have one last go.  I’m hoping a future update from Microsoft will resolve these sorts of problems.


I have had a few issues with Wireless – primarily I think due to roaming between different types of wireless networks – my initial setup was on a Windows domain and when I tried to connect wirelessly on my home network (running via a Cisco home business device) I couldn’t get a connection.  After a few days working on wired I’ve just switched back to wireless and it’s all working well (surprisingly).  So… you’re mileage may vary for wireless setups.  Let me know your experiences and I’m happy to add links to useful blogs or fixes for these sorts of issues.

I find that if wireless isn’t working that you need to disable your Wireless Virtual Switch on Windows 8 and re-enable it and you should find that the connection comes back to life.

Update 2 – Windows 8.1

I’ve been lucky enough to be running a Windows 8.1 Preview build on the same Lenovo I’ve had problems with in the past and it looks (fingers crossed) like the problem may be resolved. I haven’t got the Hyper-V environment exactly the same as my old Windows 8 build just yet but I do have Hyper-V installed. What I noticed, and perhaps this is the root cause of all the evil, is that the MAC address is being changed when I pop another VM up (currently a Windows Phone 8 emulator which uses Hyper-V) and in many environments that can cause a problem. Will keep you posted!

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