These are the steps to take for when restoring an Active Directory Domain Controller.
Active Directory Domain Controllers (DC)
You may be receiving an IP address conflict error from Microsoft when attempting to assign the correct IP for your DC to access AD. This can be because after performing a HIR (Hardware Independant Restore) hidden devices can sometimes be left behind. Following these steps should rectify the conflit error.
To solve the issue you will need to be in Active Directory restore mode. First, click Start\Programs\Accessories\CommandPrompt. When the command prompt window opens type in
set devmgr_show_nonpresent_devices=1
cd\%SystemRoot%\System32
devmgmt.msc
In Device Manager, use the right mouse click and select “Show hidden Devices”.
Then navigate to network adapters. In this section you will find that some network adapter devices are grayed out or faintly outlined. This means that these devices are not present and can be removed by clicking them and selecting uninstall.
Do not remove the "RAS ASYNC Adapter".
When the first boot of a restored DC happens hit F8 and select AD restore mode, this ensures that AD will not run. Perform all the steps below and ensure that the
correct IP address is configured to the LAN interface; this may take up to two reboots. If this is not done and the server is allowed to boot normally it will sit at the “Preparing Network Connections” for a considerable amount of time and possibly still fail.