After you install Microsoft Windows XP Service Pack 2 (SP2) and then you restart your computer, the computer is not assigned a Microsoft Internet Protocol version 6 (IPv6) global unicast address.
This problem occurs because the Ipv6.sys Windows Firewall driver cannot handle ICMPv6 Router Advertisement packets from a router when you first restart the computer after installing Windows XP SP2.
To work around this problem, you can renew the IPv6 address. To do this, follow these steps:
Click Start, click Run, type cmd, and then click OK.
At the command prompt, type ipv6 renew and then press ENTER.
After the command has completed successfully, type exit at the command prompt and then press ENTER to close the Command Prompt window.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For additional information about Internet Protocol version 6, including information about how to install or remove it, click Start, click Help and Support, type ipv6, press ENTER, and then click one of the topics to view that topic.
You can also find information about Internet Protocol 6 at the following Microsoft Web site: