Windows Server: Broadcom Network Adapter with Static IP Address Appears to Revert to DHCP

Information on a Windows server whose network adapter appears to revert to using a dynamic (DHCP) address when a static address is configured

When a static IP address is configured on a Broadcom network adapter in Windows Server, it may appear to revert to a dynamic address. The adapter's properties window will show that it is configured to obtain an address automatically; however, the output of the ipconfig /all command will show the correct static address, as does the adapter's registry key.

This occurs due to incorrect data in the following registry location:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network\Config

The following procedure deletes and recreates this registry key. This procedure is valid in Windows Server 2003, 2008, and 2008 R2.

1. Open Registry Editor (Start > Run > Regedit) and navigate to the following location:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network

2. Right-click the Config key and select Delete.
   

3. Click Yes to confirm the deletion.

   Note: Microsoft Knowledgebase article KB937056, from which most of the information in this article is taken, recommends rebooting the server at this point, but a reboot is not always necessary. If the following steps do not resolve the issue, perform the above steps again and reboot the server after deleting the Config key.

4. Open Network Connections. Right-click the affected network adapter and select Properties.
   

5. When the properties window opens, click OK to close it. This will rewrite the Config registry key without requiring a reboot of the server.