PRB: Updating MDAC Resets ODBC Registry Settings That Were Previously Set (280346)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

After you upgrade Microsoft Data Access Components (MDAC) to a later version, custom registry settings for the MSDASQL OLEDB provider may be lost. This can cause problems on systems on which these default settings have been changed to avoid certain known issues.

NOTE: Several issues can arise from using the default MSDASQL OLEDB provider settings. For more information about these issues, see the "More Information" section later in this article.

CAUSE

Upgrading MDAC to a later version resets the ODBC registry settings to their default settings or deletes settings that are not part of a default MDAC installation. This can cause problem on some systems because these settings may have been changed for performance tuning and third-party compatibility.

RESOLUTION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To resolve this issue, back up the registry keys under the following class ID in the registry before installing or updating MDAC:

HKEY_CLASSES_ROOT\CLSID\{c8b522cb-5cf3-11ce-ade5-00aa0044773d}

After MDAC has been updated and the server has been rebooted, restore this key or manually re-enter the previously changed or missing values or keys.

MORE INFORMATION

NOTE: Several issues can arise from using the default MSDASQL OLEDB provider settings, which are stored in the HKEY_CLASSES_ROOT\CLSID\{c8b522cb-5cf3-11ce-ade5-00aa0044773d} section of the registry. The following articles describe in detail the issues that can occur and the resolution to these issues. These articles contain steps to modify or to add registry keys under the HKEY_CLASSES_ROOT\CLSID\{c8b522cb-5cf3-11ce-ade5-00aa0044773d} section of the registry.

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