A program returns incorrect data or fails if the program uses the DnsQuery function to query DNS TXT records in Windows 2000 with Service Pack 4

This article has been archived. It is offered "as is" and will no longer be updated.
If a program uses the DnsQuery function to query DNS TXT records and if the DNS TXT records contain zero-length strings, the DnsQuery function returns incorrect data or causes a heap corruption. If a heap corruption occurs, the program fails with an access violation.
This problem occurs because the DnsQuery function incorrectly interprets a string with a zero-length field.

Hotfix information

A supported hotfix is available from Microsoft. 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 this specific problem.

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, submit a request to 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, visit the following Microsoft Web site: 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.


Windows 2000 Server Service Pack 4 (SP4)

Restart requirement

You must restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
   Date         Time   Version           Size     File name   --------------------------------------------------------------   09-Sep-2004  23:51  5.0.2195.6974     136,464  Dnsapi.dll          23-Mar-2004  13:47  5.0.2195.6876      92,432  Dnsrslvr.dll    
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
816915 New file naming schema for Microsoft Windows software update packages
824684 Description of the standard terminology that is used to describe Microsoft software updates

Article ID: 872802 - Last Review: 01/15/2015 08:06:44 - Revision: 1.5

  • Microsoft Windows 2000 Advanced Server SP4
  • Microsoft Windows 2000 Service Pack 4
  • Microsoft Windows 2000 Professional Edition
  • kbnosurvey kbarchive kbautohotfix kbbug kbfix kbwin2000presp5fix kbhotfixserver kbqfe KB872802