Internet Protocol Version 4: The fourth iteration of the Internet Protocol (IP) and it is the first version of the protocol to be widely deployed. IPv4 is the dominant network layer protocol on the Internet and apart from IPv6 it is the only protocol used on the Internet.

In Windows Vista, the TCP/IPv4 default gateway address is deleted when you use the Netsh command-line tool to configure the network interface IP address for the Dynamic Host Configuration Protocol (DHCP).

For example, you type the following command at a command prompt:

netsh interface ipv4 set address name=”Local Area Connection” source=dhcp

If you check the default gateway address by using the ipconfig command, you see that the IPv4 default gateway address is deleted.

Note: This problem occurs if the network interface has already configured by using DHCP.

In the properties dialog box for a network adapter, the TCP/IP Version 4 (TCP/IPv4) protocol appears to be enabled even when it is disabled. The Internet Protocol Version 4 (TCP/IPv4) check box is selected.

You run the following command to disable the TCP/IP Version 4 (TCP/IPv4) protocol on all network connections on a Windows Vista-based computer:

netsh interface IPV4 uninstall

You restart the computer, and then you view the properties of a network connection in Control Panel.

However, the Internet Protocol Version 4 (TCP/IPv4) check box is still selected. Therefore, the properties of the network connection incorrectly show that the TCP/IPv4 protocol is enabled. This behavior occurs even though you disabled the protocol from all network connections on the computer.