When you create a new switch and assign it a pyhsical Network card, you might see this error.
Error Applying New Virtual Network Changes
Setup switch failed
The switch could not bind to <physical NIC name> because it is already bound to another switch.
This might happen if you used this NIC with a switch before and later removed the switch. The physical NIC on the host is still connected to the switch Protokoll and cannot be added a second time.
Use NCPA.CPL on your host and check the properties of the physical NIC. If it’s already bound to the switch Protocol, uncheck this binding and try again.
Worked for me! Thanks.
I thought I would add some other info. I had this issue on a CORE install and don't have the option you stated, but found something that did work.
The quick and dirty solution
1. Remote desktop into the Hyper-V server
2. Find the command prompt window
This is usually located behind the blue colored Server Configuration prompt window
3. Type the following commands uninstall and reinstall the Microsoft Virtual Network Switch Protocols
C:> netcfg –u vms_pp
C:> netcfg –c p –i vms_pp
Pasted from <blog.armgasys.com