FIX: The IP address or the host header of the server that is running IIS may be returned unexpectedly when you use the Request.ServerVariables collection together with the SERVER_NAME parameter in IIS 6

Consider the following scenario. You install Microsoft Internet Information Services (IIS) 6. In IIS 6, you use the Adsutil.vbs tool to set the UseHostName metabase property or the SetHostName metabase property. You view an ASP page that is hosted on IIS 6. The ASP page uses the Request.ServerVariables collection together with the SERVER_NAME parameter. In this scenario, the IP address or the host header of the server that is running IIS may be returned unexpectedly.

This problem occurs if an ISAPI filter or an ISAPI extension calls the ServerSupportFunction function together with the HSE_REQ_EXEC_URL parameter.

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. 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, 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.

Prerequisites

You must have Windows Server 2003 Service Pack 1(SP1) or Windows Server 2003 SP2 installed to apply this hotfix.

Restart requirement

You do not have to restart the 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 item in Control Panel.

IIS 6 on Windows Server 2003 SP1, Itanium-based versionsIIS 6 on Windows Server 2003 SP2, Itanium-based versionsIIS 6 on Windows Server 2003 SP1, x64-based versionsIIS 6 on Windows Server 2003 SP2, x64-based versionsIIS 6 on Windows Server 2003 SP1, x86-based versionsIIS 6 on Windows Server 2003 SP2, x86-based versions

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

If an ISAPI filter or an ISAPI extension calls the ServerSupportFunction function together with the HSE_REQ_EXEC_URL parameter, IIS 6 does not copy the name in the alternate host name field. When this problem occurs, the host header of the server that is running IIS is returned.