Incomplete CNAME resource recordset is returned if a DNS recursive lookup fails in Windows 8 or Windows Server 2012

Applies to: Windows 8Windows 8 EnterpriseWindows 8 Pro


Consider the following scenario:
  • On a computer that's running Windows 8 or Windows Server 2012, you try to run a Domain Name System (DNS) query.
  • An incomplete alias (CNAME) resource recordset is returned if the DNS recursive lookup fails. For example, the recordset may be missing the A/AAAA record.
In this scenario, you cannot obtain the correct alias recordset in future queries of that DNS resource record for a particular time period. Additionally after the time period has expired, you still cannot successfully run a CNAME resource recordset query. This behavior occurs because the CNAME Time to Live (TTL) setting is returned from the previous failed recursive lookup.


This problem occurs because of an issue in the way that the DNS client caches the CNAME resource recordset.


Hotfix information

A supported hotfix is available from Microsoft Support. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, go to the following Microsoft website: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.


There are no prerequisites for installing this hotfix.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any previously released hotfix.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


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