HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters
| Data type | Range | Default value |
|---|---|---|
| REG_DWORD | 1 - 3 | 3 |
Determines how many times TCP sends an Address Request Packet for its own address when the service is installed. (This is known as a gratuitous ARP.) TCP sends a gratuitous ARP to determine whether the IP address it is assigned is already in use on the network.
If another computer replies to the ARP, the local computer's IP address is disabled, an error is written to the System Log in Event Viewer, and an error message is displayed to the current user. Windows 2000 starts, but it cannot operate if it is connected to the network with an address that is not unique. When the computer broadcasts to any address, it will be detected by the computer that originally held the address.
If the computer that had the IP address first is also running Windows 2000, an error message is written to its System Log and an error message is displayed to its current user.