Recently I’ve had some VMs that went trough some failovers and after that I’ve noticed that the network adapters on some of these VMs were missing in Network Connections window. Running ipconfig I was able to see the adapters and their configuration. Also some of the VMs were part of cluster and the cluster roles couldn’t be moved to the nodes where the network adapters were missing in network connections. On those VMs I couldn’t open the admin share also.
The easiest and most proper way to fix this is to shutdown the VM, remove the virtual network adapter from the VM configuration and add it again. Start the VM. Logon to the VM and reconfigure the newly added network adapter.
The above method may seems to drastic but believe me it is better than modifying WMI or Registry and definitely faster.