Symptoms
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:
%windir%\System32
Cause
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:%windir%\syswow64
%windir%\winSxS The version number for the Mfc42u.dll file in these folders is correct.
Workaround
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.
More Information
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