When your computer resolves a name that you entered as a CNAME in DNS, you receive the following error messages

•	When you try to ping the CNAME x like x.y.z.,where x.y.z. is a fully qualified domain name (FQDN): Bad IP address
•	When you use Nslookup to resolve the CNAME x x like x.y.z.,where x.y.z. is a FQDN: Can't find x.y.z.: non-existent domain

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This issue occurs because name resolution for CNAME records does not work when the corresponding "A" record resides in a delegated subzone.

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A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English-language version of this fix should have the following file attributes or later:

   Date      Time      Size     File name   Platform
   -------------------------------------------------
   12/10/99  1:58 am   178,448  dns.exe     (Intel)
   12/10/99  1:57 am   299,792  dns.exe     (Alpha)
				

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In the zonefile, move the complete "zone records" section of the parent zone below the "delegated sub-zone" section.

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Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

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