Windows 2000 / XP Disabling Auto IP-address generation

by Johannes Helmig [Published on 1 May 2001 / Last Updated on 1 May 2001]

When Windows2000/XP is configured for TCP/IP "to Obtain an IP address automatically" via DHCP, it will first attempt to locate a DHCP-server (which can takes some time ). If no DHCP
server is found on the network, it will use the build-in "Automatic Client Configuration"
(sometimes referred to as APIPA ) to assign itself an IP-address in the address-range 169.254.x.x
with Subnet- mask 255.255.0.0.

On a large network with a predefined address range, this is often not required, because it will make
the trouble-shooting of networking problems more difficult when Windows2000 / XPtakes such an
"initiative" on its own. It is possible to de-activate this feature.
(The required changes in the registry are listed on the Microsoft Knowledge base articleQ244268):


You can deactivate the AutoIPgeneration for the complete computer using the Registry-key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
Add the following value to this key: "IPAutoconfigurationEnabled", Value type: REG_DWORD
Value in hexadecimal: 0 (A value of 0 disables APIPA support on this computer) :



You can deactivate the AutoIPgeneration for just one or more network adapters:

You need to find a registry entry under:
HKEY_LOCAL_MACHINE\system\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\<adapter>


The <adapter> is listed as an internal number .
If you have problems to identify the proper adapter, see the steps below.

Create a new DWORD-key "IPAutoconfigurationEnabled" with the value set to 0 :


When restarting now Windows2000/ XP and no DHCP-server is found on the network,
no IP-address will be assigned:

in a Command-prompt window, run : ipconfig
Windows 2000 IP Configuration
Ethernet adapter Local Area Connection

 Connection-specific DNS SUffix . :
IP Address . . . . . . . . . . . . . .
Subnet Mask . . . . . . . . . . . .
Default Gateway

0.0.0.0
0.0.0.0

the IP-address "0.0.0.0" is invalid, it indicates that your system has no IP-address


How to identify the registry key for
your network adapter ?

Check in the Properties of your Network
configuration the EXACT name for your
Network card, as listed under:
Connect using :
( select it by dragging and copy it to the clipboard)

Search now the Registry for that "Adapter Description", you need to find the "ClassGUID",
a PCI-network card will be listed under
HKEY_LOCAL_MACHINE\system\CurrentControlSet\Enum\PCI :



with the "ClassGUID", search in
HKEY_LOCAL_MACHINE\system\CurrentControlSet\Control\Class\ for this class"

Check the sub-keys for the proper DriverDescription to match your network card.
and look for the Key "NetCfgInstanceID", which is identical to your <adapter> number.
if you have multiple matches showing the same DriverDescription, check under the sub-key
"Linkage" for the "UpperBind" to be "TCPIP" (just "TCPIP" , not more ! ) :

See Also


The Author — Johannes Helmig

Dr.Johannes Helmig is working as Director, Technical Knowledge Management in the Belgium office of Gerber Technology where he is involved in Customer Service and internal training, with special interest in Networking.

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