Release manifest for MDAC 2.1 ( (GA)

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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
This article discusses the release manifest of Microsoft Data Access Components (MDAC) 2.1. This article includes the following details about MDAC 2.1:
  • The known issues with MDAC 2.1.
  • The significant fixes for MDAC 2.1.
  • The frequently asked questions about MDAC 2.1.
  • The list of files that are included in MDAC 2.1 and the versions of these files.


This release manifest applies to the Internet release of the first generally available (GA) version of MDAC 2.1 ( This version is also known as MDAC (GA). This release manifest lists frequently asked questions about MDAC (GA). This release manifest describes known issues with MDAC (GA). This release manifest lists all the files that are included in MDAC (GA). This release manifest also lists the corresponding versions of these files.

For more information about installing, uninstalling, upgrading, and downgrading MDAC releases, visit the following Microsoft Developer Network (MSDN) Web site:
For more information about downloading MDAC releases, visit the following MSDN Web site:

Release version number

MDAC (GA), April 1999

Release function

This release provides the same version of MDAC that is included with Microsoft Office 2000 directly to the public.

Release ship vehicle

To download MDAC (GA), visit the following MSDN Web site:

Localization information

MDAC (GA) is currently available in the following languages:
  • U.S. English
  • German
  • Japanese
  • Korean
  • Simplified Chinese
  • Traditional Chinese
Additional languages will follow.

New features

There are no new features in this release.

Important notes

  • Internet Explorer 5a: Internet Explorer 5a installs a subset of MDAC This subset is a limited client installation that contains only core Microsoft ActiveX Data Objects (ADO), OLE DB, and Microsoft Open Database Connectivity (ODBC). The subset does not contain Microsoft Jet. The subset also does not contain any drivers or providers that MDAC (GA) has.
  • Header files: There are no changes in the header files in the different released versions of MDAC 2.x. Therefore, these files are the same in all versions.

Known issues for MDAC (GA)

The following is a summary of known issues with the MDAC (GA) release. Information is provided about known issues that include the following:
  • Microsoft Jet database engine
  • Jet 4.0 and the MDAC Access ODBC driver
  • OLE DB Provider for Jet
  • Terminal Server

Issue with the Jet database engine

MDAC (GA) contains Jet 4.0 Service Pack 1 (SP1). The version number for Jet 4.0 SP1 is 4.0.2521.08. This version of Jet is the same as the version that is included with Microsoft Office 2000. This release is a generally available release of Jet. The initial version of Jet 4.0, version 4.0.2115.25, is included in MDAC 2.1. MDAC 2.1 is released with Microsoft SQL Server 7.0. MDAC 2.1 is targeted specifically for internal use by SQL Server 7.0. Jet 4.0 SP1 contains many significant improvements over Jet 4.0 (4.0.2115.25).

For more information about data access and storage downloads, visit the following Microsoft Web site:

Issue with Jet 4.0 and the MDAC Access ODBC driver

When you install MDAC (GA), a new version of the Access ODBC driver, Odbcjt32.dll, is installed. This driver has the same file name as the MDAC 2.0 (Jet 3.5) driver. Therefore, ODBC Jet 3.5x applications are automatically upgraded to Jet 4.0 after you install MDAC (GA). This upgrade causes issues with Jet databases, with dBaseASE tables, and with Paradox tables.
Jet databases
If the Jet database, or .mdb file, remains in a version 3.5 format after you install MDAC (GA), and the version is not compacted or converted to Jet 4.0, an ODBC application may experience performance degradation. The version Jet 4.0 database engine must load the Jet 3.5 database engine to access a database that was built by using Jet 3.5. Additionally, another process converts string data to and from ANSI and Unicode. Therefore, we recommend that you convert Jet 3.5 databases to Jet 4.0 databases.

Note Concurrent users of Jet 3.5 cannot open the database after it is converted.
dBaseASE tables and Paradox tables
In versions of Jet 4.0 that are earlier than Jet 4.0, the I-ISAM drivers that access dBASE files and Paradox files experience problems with consistently maintaining indexes. Additionally, the I-ISAM drivers do not provide much support for ongoing, newer versions of these products and their file formats. Therefore, the Access ODBC Driver is upgraded to use the Borland Database Engine (BDE). The BDE is a product of InterBase. InterBase is a subsidiary of Inprise.

Users must know about certain behavior that occurs with the BDE and without the BDE:
  • When the BDE is used, the BDE is installed when you install a variety of products that are included with the BDE. Some of these products include dBaseASE, Paradox, and Delphi. Jet 4.0 automatically searches for the BDE on startup. If Jet 4.0 finds the BDE, existing Access ODBC driver applications function as before and support all BDE-supported functionality and file versions.
  • When the BDE is not used, certain functionality has changed to help preserve data integrity when dBaseASE tables and Paradox tables are accessed. This functionality is based on index support:
    • Multi-user capability is not supported for dBaseASE tables and Paradox tables. Concurrent ODBC connections to the same table, whether the connections are from the same computer or from multiple computers, are not supported.
    • The UPDATE command and the DELETE command are not supported against Paradox tables or dBaseASE tables.
    • The APPEND command is not supported for Paradox tables. APPEND inserts a single row in an existing table. Appending rows to dBaseASE tables remains supported. However, indexes are not maintained.
    • Bulk writing of data to Paradox tables is supported only when you use the "INSERT INTO ... SELECT ... FROM ..." syntax in empty tables. Indexes are not maintained.

Issue with Jet I-ISAM files and FoxPro

Microsoft FoxPro file access does not exist in dBASE Installable Indexed Sequential Access Method (I-ISAM). Because you must directly access FoxPro data through the Microsoft FoxPro ODBC driver, a single, functionally consistent path of FoxPro data files through ODBC exists. You cannot access FoxPro tables through the Access ODBC driver and xBase I-ISAM. You must create a direct ODBC data source name (DSN) to the FoxPro ODBC driver, and then you must re-create your connections. The FoxPro ODBC driver handles FoxPro indexes correctly and supports all new FoxPro file formats.

Issue with Text I-ISAM files

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.

By default, Text I-ISAM exports to the ANSI code page in Jet 4.0. In Jet 3.5, Text I-ISAM exports to the OEM code page. If you want the default code page to be any other code page, you must modify the following registry entry:
Valid values for this key include the following:
  • ANSI
  • OEM
  • Unicode
The number of any code page that has a translation installed on the operating system is also a valid value.

Issue with the Access ODBC driver and dynamic cursors

When you use the Access ODBC driver, and then you request a dynamic cursor type, the row pointer is positioned in a random row or beyond the membership of the cursor if you delete a row and then perform a MoveNext operation. This behavior can prevent an application from correctly enumerating a cursor. This behavior can also prevent the application from accessing or deleting a row that was in the original rowset. A hotfix is available for this issue. We recommend that you build or use applications that use the Access ODBC driver for any version of MDAC 2.1.

For more information about data access and storage downloads, visit the following Microsoft Web site:

Issue with OLE DB Provider for Jet

When you use the OLE DB Provider for Jet 4.0 and an ADO server-side cursor that is bound to a DataGrid object, either through an ADO DataControl control or directly to the grid, the data may not be displayed in the DataGrid object.

To resolve this error, set the IRowsetIdentity property of the recordset to True before you open the recordset. For example, you can use the following code:
rst.Properties("IRowsetIdentity") = True
You can also work around this behavior. OLE DB Provider for Jet does not support the DBPROP_LITERALIDENTITY property. Therefore, this provider must implement the IRowsetIdentity interface. ADO must set this property before the rowset is opened. If you query for an interface such as the IRowsetIdentity interface, but OLE DB does not open the rowset to support this interface, you receive the E_NOINTERFACE error message even if the provider supports the interface.

Issue with Terminal Server

When you install the MDAC 2.1 redistributable components on a computer that is running Microsoft Terminal Server, the access control lists (ACLs) are changed on all files that MDAC installs in the System32 folder. Before you install the MDAC 2.1 redistributable components, everyone has Read access. However, after you install the MDAC 2.1 redistributable components, the user who just installed MDAC has Full Control access, and no other users have access.

To correct this problem, you can download the Mdac.txt batch file. This file is used to complete the installation of MDAC on a Microsoft Windows NT 4.0 Terminal Server computer.

After you install MDAC (GA), copy the Mdac.txt file to the System32 folder on your computer, and then rename the Mdac.txt file as Mdac.cmd. You can run the renamed file at the command prompt. To this, click Start, click Run, type system32\mdac.cmd, and then click OK.

For more information about the Mdac.txt batch file, visit the following Microsoft Web site:

Significant fixes

The following is a summary of known issues and significant fixes that are incorporated in the MDAC (GA) release.

These fixes are specific to MDAC and to Microsoft Access 2000, Microsoft Outlook 98, Microsoft Outlook 2000, and Microsoft Office Web services.

General fixes

The initial release of Internet Explorer 5 (build 5.00.2014.0216) contains MDAC (IE5). This release of Internet Explorer 5 may generate an application violation when an ADO consumer application tries to connect to a data source, or when you try to test a connection by using the Microsoft Data Links API. Specifically, this issue affects those OLE DB providers that do not have the optional OLEDB_SERVICES registry entry. This issue adversely affects Microsoft OLE DB Provider for DB2 and Microsoft OLE DB Provider for AS/400 and Virtual Storage Access Method (VSAM). This problem is resolved in Internet Explorer 5 build 5.00.2314.1003 and in MDAC (GA).

Backward compatibility fixes

Significant fixes were implemented in this release of MDAC. This release also includes fixes that are specific to MDAC and Access 2000, to Outlook 98, to Outlook 2000, and to Office Web services. The following fixes involve backward compatibility with MDAC 2.1:
  • An incompatibility exists with older ODBC drivers.

    You may install Microsoft Internet Explorer 5 on a computer that already has MDAC 2.0 installed. Then, you may run an application that tries to access Jet data by using ADO through OLE DB Provider for ODBC. If the application tries to update a fixed-length numeric field, such as a currency field, in the Jet database, the operation is not successful.

    Internet Explorer 5 installs core MDAC 2.1, including OLE DB Provider for ODBC. Internet Explorer 5 does not install MDAC 2.1 ODBC Driver for Jet. The problem occurs when you use OLE DB Provider for ODBC 2.1 and you use version 2.0 of the ODBC driver. OLE DB Provider for ODBC 2.1 is incompatible in this way with the older ODBC driver. OLE DB Provider for ODBC has been updated to work with the older ODBC driver. Fixing this problem also resolves some related but less serious regressions.
  • The record is not deleted when you delete a record in a sorted data page.

    When you delete a record in a sorted data page, the record is not deleted. If you change a sorted page, and then you cancel the change before you save the change, the changed value still appears on the page. Both errors were resolved by adding missing query interface (QI) support for an implemented interface in the cursor engine.
  • An uninitialized variant occurs in ADO.

    A filter on the schema rowset causes the VariantClear function to generate an access violation.
  • A server cursor error occurs in ADO.

    When you use any OLE DB provider to work with an ADO recordset that is associated with a server cursor, the following behavior occurs when you try to delete a record on certain rows:
    • The MoveNext method moves the cursor to a position that is three records after the position that the DeletedRecordPosition value specifies.
    • The MovePrevious method moves the cursor to a position that is two records before the position that the DeletedRecordPosition value specifies.
    This behavior is incorrect because the cursor pointer does not move to the record that immediately follows or comes before the previously deleted record. This behavior would have occurred if the record had not been deleted.

    This behavior may affect users who write ADO code behind Access 2000 forms.
  • An error occurs in a client-side cursor.

    When you use a client-side cursor, data corruption occurs when you insert more than 4096 rows.
  • An application violation occurs in Msadce.dll.

    When you run a SHAPE query after you connect to a data source by using a .udl file and client-side cursors, an application violation occurs in Msadce.dll. SHAPE queries that use providers that are connected to a data source by using a .udl file cause an access violation.
  • An application violation occurs in ADO.

    When you call GetIndex on a recordset that has no index set, an application violation occurs in ADO. This affects providers that have index support through the IRowsetIndex interface.

Fixes for incompatibility and installation problems

The following problems have been resolved:
  • You cannot install Microsoft Office 95.

    You cannot install Microsoft Office 95 if you installed Microsoft Office 2000 because the ODBC driver in the installation folder is incompatible with the ODBC driver for Jet that MDAC 2.1 installs.
  • You cannot install Microsoft Visual InterDev 97.

    You cannot install Microsoft Visual InterDev 97 if you installed Office 2000 or earlier versions because of an incompatibility between the ODBC driver in the installation folder and the ODBC driver for Jet that MDAC 2.1 installs.
  • You cannot install Crystal Reports 7.0 Professional.

    An error occurs when you try to install Crystal Reports 7.0 Professional after you install MDAC 2.1. This error occurs because a bug in the version checking code is invoked when two instances of the Odbccp32.dll file are loaded. One version of the Odbccp32.dll file is in the installation folder, and the other version of the Odbccp32.dll file is the previously installed version.

File list for MDAC (GA) April 1999

Collapse this tableExpand this table
File nameLong file nameAlpha versionx86 version
Cliconf.hlp n/a n/a
Dbmsshrn.dll1998.11.13.0 1998.11.13.0
Drvvfp.cnt n/an/a
Drvvfp.hlp n/an/a
Ds16gt.dll 3.510.3711.03.510.3711.0
Ds32gt.dll 3.510.3711.03.510.3711.0
Handsafe.reg n/an/a
Handunsf.reg n/an/a
Instcat.sql n/an/a
Jroread.txt JROreadme.txt n/an/a
Makapt15.bat n/an/a
Makfre15.bat n/an/a
Msadce.dll 2.10.3711.02.10.3711.0
Msadcer.dll 2.10.3711.02.10.3711.0
Msadcf.dll 2.10.3711.02.10.3711.0
Msadcfr.dll 2.10.3711.02.10.3711.0
Msadco.dll 2.10.3711.12.10.3711.1
Msadcor.dll 2.10.3711.02.10.3711.0
Msadcs.dll 2.10.3711.0 2.10.3711.0
Msadds.dll 2.10.3711.2 2.10.3711.2
Msaddsr.dll2.10.3711.0 2.10.3711.0
Msader15.dll 2.10.3711.3 2.10.3711.3
Msado15.dll 2.10.3711.9 2.10.3711.9
Msado20.tlb n/an/a
Msadomd.dll 2.10.3711.0 2.10.3711.0
Msador15.dll 2.10.3711.3 2.10.3711.3
Msadox.dll 2.10.3711.0 2.10.3711.0
Msadrh15.dll 2.10.3711.3 2.10.3711.3
Msdadc.dll 2.10.3711.2 2.10.3711.2
Msdaenum.dll 2.10.3711.2 2.10.3711.2
Msdaer.dll 2.10.3711.2 2.10.3711.2
Msdaora.dll 2.10.3711.0 2.10.3711.0
Msdaosp.dll 2.10.3711.0 2.10.3711.0
Msdaprsr.dll 2.10.3711.0 2.10.3711.0
Msdaprst.dll 2.10.3711.0 2.10.3711.0
Msdaps.dll 2.10.3711.0 2.10.3711.0
Msdarem.dll 2.10.3711.0 2.10.3711.0
Msdaremr.dll 2.10.3711.0 2.10.3711.0
Msdasc.cnt n/a n/a
Msdasc.dll 2.10.3711.2 2.10.3711.2
Msdasc.hlp n/a n/a
Msdasc.txt Msdasc.txt n/a n/a
Msdasql.dll 2.10.3711.0 2.10.3711.0
Msdasqlr.dll 2.10.3711.0 2.10.3711.0
Msdatl2.dll 2.10.3711.0 2.10.3711.0
Msdatsrc.tlb n/a n/a
Msdatt.dll 2.10.3711.02.10.3711.0
Msdfmap.dll 2.10.3711.02.10.3711.0
Msdfmap.ini n/a n/a
Msdsqlrm.txt Msdasqlreadme.txt n/a n/a
Msexch40.dll 4.0.2521.8
Msexcl40.dll 4.0.2521.8
Msjet40.dll 4.0.2521.94.0.2521.8
Msjeto~1.dll Msjetoledb40.dll 4.0.2521.8 4.0.2521.8
Msjint40.dll 4.0.2521.8 4.0.2521.8
Msjro.dll 2.10.3711.0 2.10.3711.0
Msjter40.dll 4.0.2521.8 4.0.2521.8
Msjtes40.dll 4.0.2521.8 4.0.2521.8
Msltus40.dll 4.0.2521.8
Msltus40.dll n/a n/a
Msorcl32.dll 2.573.3711.0 2.573.3711.0
Msorcl32.hlp n/a n/a
Msorcolr.txt Msorcloledbreadme.txt n/a n/a
Msorcrdm.txt Msoracle32readme.txt n/a n/a
Mspbde40.dll 4.0.2521.8
Msrclr40.dll 4.0.2521.8
Msrd2x40.dll 4.0.2521.8
Msrd3x40.dll 4.0.2521.8
Msrecr40.dll 4.0.2521.8
Msrepl40.dll 4.0.2521.9
Mstext40.dll 4.0.2521.8
Mswdat10.dll 4.0.2521.8 4.0.2521.8
Mswstr10.dll 4.0.2521.8 4.0.2521.8
Msxactps.dll 2.10.3711.0 2.10.3711.0
Msxbde40.dll 4.0.2521.8
Mtxdm.dll 1997.11.532.01997.11.532.0
Mtxoci.dll 1998.2.715.01998.2.715.0
Odbc16gt.dll 3.510.3711.03.510.3711.0
Odbc32.dll 3.510.3711.03.510.3711.0
Odbccp32.cpl 3.510.3711.0 3.510.3711.0
Odbccp32.dll 3.510.3711.0 3.510.3711.0
Odbccr32.dll 3.510.3711.0 3.510.3711.0
Odbccu32.dll 3.510.3711.0 3.510.3711.0
Odbcinst.cnt n/a n/a
Odbcinst.hlp n/a n/a
Odbcint.dll 3.510.3711.0 3.510.3711.0
Odbcjet.cnt n/a n/a
Odbcjet.hlp n/a n/a
Odbcji32.dll 4.0.3711.64.0.3711.6
Odbcjt32.dll 4.0.3711.8 4.0.3711.8
Odbctrac.dll 3.510.3711.0 3.510.3711.0
Odexl32.dll 4.0.3711.6 4.0.3711.6
Odfox32.dll 4.0.3711.6 4.0.3711.6
Odpdx32.dll 4.0.3711.6 4.0.3711.6
Odtext32.dll 4.0.3711.6 4.0.3711.6
Oledb32.dll 2.10.3711.9 2.10.3711.9
Oledb32r.dll 2.10.3711.2 2.10.3711.2
Oledb32x.dll 2.10.3711.2 2.10.3711.2
Sqlstr.dll 1998.11.13.0 1998.11.13.0
Sqlwid.dll 1998.11.13.0 1998.11.13.0
Sqlwoa.dll 1998.11.13.0 1998.11.13.0
Vfpodbc.dll 6.0.8428.0 6.0.8428.0
Vfpodbc.txt n/a n/a
Asycfilt.dll 2.40.4275.1 2.40.4275.1
Msvcirt.dll 6.0.8178.0 6.0.8168.0
Msvcrt.dll 6.0.8441.0 6.0.8397.0
Oleaut32.dll 2.40.4275.1 2.40.4275.1
Olepro32.dll 5.0.4275.1 5.0.4275.1
Stdole2.tlb 2.40.4275.1 2.40.4275.1


For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
232060 MDAC setup troubleshooting guide
For more information about MDAC support, including information about ADO, OLEDB, ODBC, visit the following Microsoft Web site:;[LN];mdac
For more information about product downloads and update downloads, visit the following MSDN Web site:
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.


Article ID: 842279 - Last Review: November 16, 2007 - Revision: 3.7
  • Microsoft Data Access Components 2.1
kbinfo KB842279

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