A. APIPA (Automatic Private IP Addressing) was discussed in 'Q. My Windows 2000 DHCP client has an IP address not in any scopes, how?' and is the mechanism in a small network that clients will automatically allocated themselves an IP address in the range of 169.254.x.x if no DHCP server can be contacted.

It may be desirable to disable this and to do this perform the following:

  1. Start the registry editor (Regedit.exe)
  2. Move to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces
  3. Select the required interface
  4. From the Edit menu select New - DWORD value
  5. Enter a name of IPAutoconfigurationEnabled and press Enter
  6. Double click the new value and set to 0. Click OK
  7. Close the registry editor

If you have multiple adapters and wish to disable for all just create and set HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\IPAutoconfigurationEnabled to 0.