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Article ID: 933339 - Last Review: July 1, 2010 - Revision: 2.0


When you apply security update MS07-012, the version number of the Mfc42u.dll file is not updated. The Mfc42u.dll file is located in the following folder:


This issue occurs because the updated version of the Mfc42u.dll file that is included for the Microsoft Windows operating systems that are listed in the "Applies to" section does not use a newer version number. The older version number (6.5.9146.0) is used on these Windows operating systems.

Note The Mfc42u.dll file may also be located in folders other than the %windir%\System32 folder. For example, the Mfc42u.dll file may also be located in the following folders:
The version number for the Mfc42u.dll file in these folders is correct.


The security update for the Windows operating systems that are listed in the "Applies to" section is correctly offered on the Windows Update Web site. The update is offered despite the incorrect version number. Therefore, no additional action is required.


For more information about security update MS07-012, click the following article number to view the article in the Microsoft Knowledge Base:
924667  ( ) MS07-012: Vulnerability in Microsoft Foundation Classes could allow for remote code execution
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use ( for other considerations.

  • Microsoft Windows Server 2003 Service Pack 1, when used with:
    • Microsoft Windows Server 2003, Enterprise x64 Edition
    • Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems
  • Microsoft Windows XP Professional x64 Edition
  • Microsoft Security Essentials
kbexpertiseinter kbexpertisebeginner kbsecurity kbtshoot kbPubTypeKC kbprb KB933339
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