Win 8.1

The symptom is 2 adapters in Device Manager that I can't remove:

From time to time, this problem interferes with the Ethernet card on the PC, and I lose all connectivity for the host OS.  So I really need to fix this.  I've currently recovered connectivity by deleting my VM and the virtual switch in Hyper-V manager, but I'd like to resolve this problem properly by eliminating these 'unattached' adapters.

I've read many posts and still am not convinced I know which steps to take.  Many of the posts seem a little dated, so I'm concerned I'll create additional problems if I follow old stuff.  Here are a few of the solutions I've seen on the boards:

1) edit the registry, up to 50 times.  This doesn't sound like a great idea but if that's what it takes... https://social.technet.microsoft.com/forums/windowsserver/en-US/20e826af-b484-48d8-ac24-c3e7c4cc30fd/cannot-remove-ms-virtual-network-switch-adapter-leftover-of-hyperv  and  https://social.technet.microsoft.com/Forums/windowsserver/en-US/f6673b1e-f8dc-47c9-80ff-178db17b2962/hyperv-networking-woes?forum=winserverhyperv

2) remove the adapter in something called the Administrative Website.  I don't really know what that is.  Is that a current piece of software for use with Hyper-V on Win 8+?  I have been using the Hyper-V manager.  Is that not good enough?  If Administrative Website is relevant, where do I find a copy for Win 8.1? https://technet.microsoft.com/en-us/library/cc708372%28v=ws.10%29.aspx?f=255&MSPPError=-2147217396

3) I tried to uninstall Hyper-V and couldn't.  I went through Control Panel > Programs and Features > Turn Windows features on or off and unchecked Hyper-V.  When the process was over, I could still run Hyper-V even though the checkbox is cleared out in the Windows Features panel.  I wonder what's going on there.

4) Other suggestions were to go to a restore point, or even worse, refresh the system, thereby removing everything else as well.  There must be an explanation for what's happening here that doesn't involve nuking my workstation.

So, if someone could get me started on fixing this I would appreciate it.  I had this problem once before and was able to remove Hyper-V which cleared the adapters from Device Manager, but I can't do this now because of item #3 above.

Thanks for your help in advance.

Those bindings are created when you create an External Virtual Switch and select the option "allow the management OS to share.."

If you do not have an External or Internal Virtual Switch defined in the Hyper-V Virtual Switch manager, the devices should not exist.  They come and go.

As far as item #3.  Removing Hyper-V and the Hyper-V Management Tools should remove Hyper-V - meaning that you should not be able to run any VMs or manage Hyper-V.  But you would still be able to open Hyper-V manager if you left it installed under the RSAT tools.

If you removed Hyper-V while you had virtual switches configured, you might leave some artifacts behind.  This might be the situation you are in.  search for nvspscrub.  it is a vb script that should cleanse things.

Hi Brian,

Thanks for your response.

I have 'restored' my workstation.  I put quotes around 'restored' to denote that Device Manager no longer has the errant adapter entries, the workstation is connecting to the network just fine, and Hyper-V is re-installed.  But it was touch and go for a while.

I had to go through an 'install and uninstall Hyper-V' cycle about 3 times before Hyper-V was installed correctly.  It was bizarre; there was a moment when the Windows Features panel seemed out of sync with the status of the Hyper-V feature.  The box was cleared, yet Hyper-V was working.  Then when I checked the box and 'installed' it, Hyper-V didn't work.  Although concerned, I just kept installing and uninstalling through 'Turn Windows features on or off' and eventually the installed feature 'synced up' with the checked status in the Windows Features panel.  The Device Manager status fixed itself early in this process.

So now I'm about to reinstall my VM using the existing VHD.  Of course I have to create a virtual switch and that's where I'm now concerned. 

Dell suggests don't check 'Allow management operating system to share this network adapter' (http://www.dell.com/support/article/us/en/19/SLN288347/EN).  There are also a great many posts on the net that suggest 'allow the host to share the adapter' creates instability (https://social.technet.microsoft.com/Forums/windowsserver/en-US/d6e1736d-c17e-4c17-beaf-8afb0fd8927a/unstable-system-due-to-use-of-allow-management-operating-system-to-share-this-network-adapter?forum=windowsserver2008r2virtualization).  And if I try to create the switch without checking this option I get the following message:

But I only have one Ethernet adapter on this machine, so don't I have to allow the host access? (http://fixmyitsystem.com/2013/01/PowerShell-AllowManagementOS.html)

I don't understand the implications of all this and wondered if you could help?

Also, when it says it 'deletes any static settings', is that just during the setup?  I.E., afterwards can I go back in and reset the static settings?

I'm holding off recreating the VM until I have a better understanding of this.  Thanks.

The thing to not do is allow Hyper-V to automatically create a virtual switch when the role is added.  That has had problems for years.

This is what Dell should be advising you against.

Beyond that, using 'allow management os to share" has been pretty stable since 2012 R2.

And yes, you will get the warning, if you are not remotely managing the box you will still be able to manage it.  But, if you don't 'allow management o's to share" when you create the external virtual switch, then your management os won't be about to reach anything.

If the VM configuration still exists (which it should if you didn't delete it) you should be able to just import it.