Sometimes there is a problem especially when switching network cards in virtual machines, that the old card remains hidden with it’s ip-config. If you want to configure a new device with the same IP-Address, you will get a warning that this IP-Address is already used on another interface. Of course you can’t delete the configured IP-Address, because the old device is not available anymore and somewhere hidden.
Now you can try to fiddle in the registry, but there is a clean way:
Start a command prompt as Admininstrator and then enter:
set devmgr_show_nonpresent_devices=1 start devmgmt.msc
Now you have to enable “Show hidden devices” in the menu of Device Manager and tadaaa, you see all devices which are not existing anymore. If you do not see the devices, make sure you start devmgmt.msc from the same cmd window where you set the devmgr_show_nonpresent_devices variable.
You can now remove the unused devices.
This setting is not permanent and stays only within this command line session.