Some Microsoft Data Access Components (MDAC) files in the %WinDir%\System32\Dllcache folder may not be updated when you run the MDAC Setup program.

When this problem occurs, Microsoft Windows File Protection (WFP) restores older versions of the MDAC files from the Dllcache folder if you make any changes to the primary MDAC files. Therefore, WFP may replace the newly installed MDAC files. Changes that may cause WFP to replace the newly installed files include renaming files or deleting files.

This section describes how to resolve the version restore problems that are described in the "More Information" section. The troubleshooting steps may be different on your computer, depending on the MDAC version that you are using.

• If you are not using the latest version of MDAC, follow these steps to resolve the problem:
  1. Stop any applications or services that are using MDAC components, and then upgrade your MDAC components to the latest version.
  2. If the process list appears while you are running the MDAC Setup program, close all processes that appear in the list before you continue the Setup program.
  Warning We recommend that you first test your program with any later MDAC version in a test environment to make sure that you know about any compatibility issues before you upgrade your production servers.
• If you are currently using Microsoft Windows Server 2003, you may have to reinstall the operating system to resolve the problem. MDAC 2.8 is included with Windows Server 2003. Currently, no later version of MDAC exists to upgrade to. The MDAC Setup program does not let you install an MDAC version that is the same as or older than the version that is included with the operating system.

For more information about this problem, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site: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 usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

When you install MDAC, the MDAC Setup program displays a list of processes that are currently using any MDAC files. If you choose to ignore this warning and to continue the setup process, you must restart your computer after the Setup program has completed. When you restart your computer, the MDAC files that were in use while the Setup program was running are updated. However, a problem in Windows File Protection may cause the file update process to fail.

If the files are not updated correctly, and you make a change to any one of the primary MDAC files, Windows File Protection may restore files from the Dllcache folder and overwrite the newly installed files.

Note The primary MDAC files are not located in the Dllcache folder.

You will not experience this problem if you close all processes that appear in the list when you run the MDAC Setup program.

For more information about Windows File Protection, visit the following Microsoft Developer Network (MSDN) Web sites: