A Client Certificate on One Request Handle May Interfere with Secure Sockets Layer (SSL) Negotiations on Other Request Handles When You Use WinHTTP

When you use Microsoft Windows HTTP Services (WinHTTP), setting a client certificate on one request handle may interfere with Secure Sockets Layer (SSL) negotiations on other request handles that are sent to the same host or to the same port. As a result, if Microsoft SharePoint Portal Server is installed on the server, the Microsoft SharePointPS Search service does not crawl certain pages of the portal site that use a client certificate.

This issue occurs because, in a session, WinHTTP incorrectly processes concurrent SSL client authentication negotiation operations that use the same host or the same port.

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

No prerequisites are required.

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) 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.

To work around this problem, do one of the following, as appropriate to your situation:

• Open a different session for each virtual directory on the server that requires a client certificate.
  
  -or-
• Serialize the SetOption(CERT_CONTEXT) call in a session, and do not call WinHTTP when either a SendRequest or a ReceiveResponse call is in progress in the session.

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