After you use a smart card to unlock a Windows XP-based computer, you are prompted for authentication when you access resources that require NTLM authentication

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Consider the following scenario:
  • You configure an Active Directory domain so that domain users must use a smart card to log on to the domain.
  • In this domain, some resources require NTLM authentication. Additionally, these resources do not accept Kerberos authentication.
  • On a Windows XP-based client computer, a user uses a smart card to log on to the computer. Then, the user locks the computer.
  • On the domain controller, you change the password for the smart card user account while the Windows XP-based client computer is locked.
  • The user uses the smart card to unlock the computer and to then work online.
In this scenario, the user is prompted for authentication when he or she accesses resources that require NTLM authentication. Additionally, the user is not prompted to synchronize the smart card user account credentials.

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.


To apply this hotfix, you must have Windows XP Service Pack 2 installed.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other previously released hotfixes.

Registry information

To use this hotfix, you do not have to make any changes to the registry.

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.
Windows XP with SP2, x86-based versions
File nameFile versionFile sizeDateTimePlatformSP requirement
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More information
In some cases, a Windows XP-based computer does not request Kerberos tickets after you unlock the computer by using the standard user name and password.

For more information, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
smartcard denied unlock access

Article ID: 939850 - Last Review: 01/16/2015 09:43:50 - Revision: 3.0

  • Microsoft Windows XP Professional
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