Automatic Private Internet Protocol Addressing (APIPA)

Automatic Private Internet Protocol Addressing is a function of Windows 98. It provides Internet Protocol (IP) addresses to computers in a Local Area Network (LAN), either when there is no Dynamic Host Configuration Protocol (DHCP) server or the usual DHCP server is down.

Addresses are assigned in the range 169.254.0.0 to 169.254.255.255

Addresses in this range are reserved for this purpose and are not valid over the Internet. If connecting to the Internet, obtain IP addresses from your Internet Service Provider (ISP).

This address allocation detects conflicts via a Network Basic Input/Output System (NetBIOS) naming broadcast ensuring that each machine gets an IP address in the above range that is not in use. The address is randomly chosen initially.

Follow these instructions to disable Automatic Private Internet Protocol Addressing

  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