IP address is alreay assigned to another adapter.

Error when assigning static IP adress to your NIC card.

I'm sure that you're already saw this message.

The IP address XXX.XXX.XXX.XXX you have entered for this network adapter is already assigned to another adapter Name of adapter. Name of adapter is hidden from the network and Dial-up Connections folder because it is not physically in the computer or is a legacy adapter that is not working.

In fact the in the KB from VMware that I found, shows you what to do in case you see this message when wanting to assign a static IP adress to your VM. And this happens quite often since not only the P2V process is the principal cause of the trouble.  This happens when:

– you did P2V conversion of your physical server and the physical network card stays registered in the registry and hidden in the Device manager.
– you upgrade to a new version of virtual hardware.
– you added or removed network adapters several times.

In all those above situations you'll end up with an error like that.

To solve the trouble,  you need to get rid of this ghosted NIC card, but first you must see it in the Device Manager…. The process of  how to show ghosted devices in Device Manager and how to remove them has already been documented on my blog, but I don't think that it's been associated with such an error and context. So It's never too late to remember what to do to remove those devices.

01. Open command prompt and type: set devmgr_show_nonpresent_devices=1

02. Still during you're in the command window type: devmgmt.msc

03. Now when you open Device Manager and in the menu you'll choose show hidden devices, you'll see all the devices which are no longer present in the VM and you can remove them.

Another way to do is to use devcon utility from Microsoft. To do so follow the steps:

01. Download the DevCon tool from Microsoft KB Article 311272.
02. Unpack the 32bit or 64bit DevCon tool binary to a local folder.
03. Click Start > Run.
04. Type cmd and press Enter.
05. Type CD:path_to_binaries to navigate to the devcon.exe is located.
06. Use the following syntax to find installed network adapters:

1. devcon findall *net* or devcon listclass net

Note: In the output of the previous commands, there is a line for the ghosted network adapter that is similar to PCI.

07. Run the following command to remove the adapter:

1. devcon remove @devicename

For example, devcon remove “@PCIVEN_14E4&DEV_1600&SUBSYS_01C21028&REV_024&378EDFA4&0&00E2” .

Note: IDs that include an ampersand character (&) must be enclosed in quotation marks as seen in the example

08. Reboot the system and you no longer see the ghost network adapters.

Source: VMware KB 1015572 – Networking Error: IP address already assigned to another adapter