DHCPv6 client may fail to be assigned an IPv6 address

Applies to: Windows Vista UltimateWindows Vista Home BasicWindows Vista Business


Your computer is connected to a network that supports IPv6 connections, but fails to be assigned an IPv6 address using DHCP. Your Internet Service Provider (ISP) may indicate you have a duplicate DHCPv6 DUID and point you to this article for resolution.


In November 2012, Microsoft released updates on Windows Update to resolve this issue:

Windows 7 and Windows Server 2008 R2

The solution was released in this update http://support.microsoft.com/kb/2763523

Windows 8 and Windows Server 2012

The solution was released as part of this update http://support.microsoft.com/kb/2770917 

If you cannot install these updates or you are using Windows Vista or Windows Server 2008, you can still use the solution below to resolve the issue. 

To have us fix this problem for you, go to the "Fix it for me" section. If you prefer to fix this problem yourself, go to the "Let me fix it myself" section.

Fix it for me

To fix this problem automatically, click the Fix it button or link. Then click Run in the File Download dialog box, and follow the steps in the Fix it wizard.

  • This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
  • If you are not on the computer that has the problem, save the Fix it solution to a flash drive or a CD and then run it on the computer that has the problem.

Then, go to the "Did this fix the problem?" section.

Let me fix it myself

Delete the registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\TCPIP6\Parameters\Dhcpv6DUID and reboot the computer. To do this, perform the following steps: 
  1. Open Registry Editor
  2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\TCPIP6\Parameters
  3. Right click and delete the entry named Dhcpv6DUID
  4. Reboot the computer
NOTE: Please ensure that you make a backup of the registry / affected keys before making any changes to your system.

Did this fix the problem?

  • Check whether the problem is fixed. If the problem is fixed, you are finished with this section. If the problem is not fixed, you can contact support.
  • We would appreciate your feedback. To provide feedback or to report any issues with this solution, please leave a comment on the "Fix it for me" blog or send us an email message.