Cannot assign IP address to a NIC after a physical to virtual conversion because a duplicate IP exists

Symptoms

• After a physical to virtual (P2V) conversion of a machine, you cannot assign an IP address to a NIC
• A message indicates that the IP already exists in the network, but no other machine in the network is sharing the IP

Resolution

Sometimes after a P2V conversion, the drivers for the physical NICs are still present and the physical NIC is still present as a device on the machine. These ghost NICs still have the old IP address and the virtual NIC cannot be assigned the same IP address.

To resolve this issue, follow these steps inside the guest operating system:

1. Click Start > Programs > Accessories > Command Prompt.
2. Type the following command and press Enter:
   
   set devmgr_show_nonpresent_devices=1
   
   
3. Type the following command , and press Enter:
   
   start devmgmt.msc
   
   
4. Click View > Show hidden devices.
5. Expand Network adapters. The old physical network cards are grayed out.
6. Right-click on these NICs and click Uninstall.
7. Once all of the grayed out NICs are uninstalled, assign the IP address to the virtual NIC.

Note: When you close the command prompt window, Windows clears the devmgr_show_nonpresent_devices=1 variable that you set in step 2 and prevents ghosted devices from displaying when you click Show hidden devices. If you are a developer or power user and you want to view devices that are not connected to your computer, set this environment variable globally:

1. Right-click My Computer.
2. Click Properties.
3. Click the Advanced tab.
4. Click the Environment Variables tab.
5. Set the variables in the System Variables box.