Additional Prompts for a Client Certificate with Internet Explorer 6 Service Pack 1 (330338)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you are using Internet Explorer 6 Service Pack 1 (SP1), you may be prompted multiple times to select a client certificate. This issue typically occurs when you open an unsecured document (with an HTTP address) that hosts one or more IFRAMEs, with each IFRAME pointing to a secured document (with an HTTPS address). This issue does not occur with Internet Explorer 6 or Internet Explorer 5.5.

RESOLUTION

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. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Internet Explorer 6 service pack that contains this fix.

To resolve this problem immediately, 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:

http://support.microsoft.com/contactus/?ws=support

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 typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix has the file attributes (or later) 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
   -------------------------------------------------------
   19-Dec-2002  12:16  6.0.2800.1149  585,728  Wininet.dll

MORE INFORMATION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

This problem is a side-effect of a security fix in Internet Explorer 6 SP1. The hotfix that is described in this article installs a new registry key to disable the code that is added by the security fix:

HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings
CertCacheNoValidate: REG_DWORD: 1

For security reasons, Microsoft recommends that you implement a server-side solution instead of using this hotfix. To use a server-side solution, avoid hosting HTTPS frames in pages that are accessed from an HTTP address.