MDAC 2.1 OLE DB Provider for ODBC Fails With Drivers That Don't Support SQLExendedFetch()

When using the MDAC 2.1 OLE DB Provider for ODBC (MSDASQL) against an ODBC driver that does not support SQLExtendedFetch(), the driver may fail with the following error:
This error does not occur with the OLE DB Provider for ODBC that released with MDAC 2.0.

The OLE DB Provider for ODBC incorrectly attempts to set the SQL_ATTR_ROW_ARRAY_SIZE statement attribute before checking to see if it is supported by the ODBC driver. This attribute is not supported in a driver that does not implement SQLExtendedFetch().

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Microsoft Data Access Components Service Pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. 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 typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later:

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

IMPORTANT: You cannot install this hotfix on a machine that is currently running MDAC 2.1 SP1 GA (version 2.10.3711.11) or earlier. You must install MDAC 2.1 SP2 GA (version 2.10.4202) in order to use this hotfix.

In order to alleviate memory fragmentation problems, significant code changes were made to Msdatl2.dll, which this provider is linked with. If this hotfix is installed on a machine that is running MDAC 2.1 SP1 GA (2.10.3711) or earlier, the provider will not load and attempts to register it will fail. Please see the REFERENCES section below for more information

Manual Installation

Use the following steps to manually install Msdasql.dll:

1. Close or stop any applications or services that are using Msdasql.dll. This may include Internet Information Server (IIS), Microsoft Transaction Server (MTS), Microsoft Distributed Transaction Coordinator (DTC), and any ADO or OLE DB applications.
2. Download the hotfix version of Msdasql.dll into a temporary directory and run it to extract the following files: Msdasql.dll and Readme.txt.
3. Locate and rename the current version of Msdasql.dll, which should be in the \Program Files\Common files\System\Ole db folder.
4. Copy the hotfix version of Msdasql.dll into the same location, and restart your services and applications.

Important Notice for Windows 95 and Windows 98 Users

If you are installing this fix onto a computer running Windows 95 or a computer with the original release of Windows 98, you may need to install the Windows 98 Migration DLL included with this fix. Please carefully read the Migrate_qfe.txt file that is included Migration.exe file included with the download.

REFERENCES

For more information on the memory fragmentation issue referenced above, see the following article in the Microsoft Knowledge Base: