Using 64-bit Applications with Microsoft Access Database Files

The Microsoft Jet database engine dates back to Windows 95 or earlier and was the original underlying database engine for *.mdb files created with Microsoft Access. Versions of Jet are contained in all editions of Microsoft Windows through Windows 7 and are used by 32-bit applications to connect to Access databases contained in *.mdb files.

Beginning in Office 2007, Microsoft Access gained a new file format with file extension *.accdb and additional functionality. Access 2007 (and later) database files are supported by the new Microsoft ACE (Access Database Engine) driver.

The Microsoft Jet database engine is considered a deprecated product. Although it is still contained in Windows 7, no plans have been announced for it to be ported to a 64-bit version. The Microsoft ACE database engine is available in a version for 64-bit systems and can be downloaded directly (driver only) at:

The Microsoft ACE database engine can also be downloaded as part of the x64 version of Microsoft Office 2010 at:

There is currently an unfortunate limitation of the 64-bit ACE driver – it cannot co-exist with 32-bit versions of Microsoft Office.

The 64-bit versions of Altova MissionKit applications currently require the x64 Microsoft ACE driver to open Access databases, regardless of whether the file extension is *.mdb or *.accdb.

Existing files created with 32-bit versions of Altova applications, such as MapForce mappings or StyleVision stylesheets, may contain connection information that specifies the 32-bit Jet OLEDB provider (Microsoft.Jet.OLEDB.4.0). Altova 64-bit applications will automatically convert these older files to ACE driven connections (Microsoft.ACE.OLEDB.12.0). Users only need to install the 64-bit ACE driver, as described above.

The screen shots below show various scenarios on a system running a 64-bit version of Windows 7:

No 64-bit driver available

64-bit driver with *.accdb file

64-bit driver with *.mdb file

Click here for more information about 64-bit versions of Altova software.

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