Symptoms
DAO is a COM wrapper around the Jet Engine, which is used by MicrosoftAccess, Excel, Project, Visual Basic, and the Microsoft Foundation Classes(among others). It can be confusing which version of Jet you are usingbecause so many applications may distribute Jet onto your machine. Thetables and explanations in this article are intended to help you identifythe version and components of Jet that you are using for the givenapplication.
Resolution
This table displays which version of Jet is shipped with each of thefollowing products.

ApplicationMicrosoft JET version———————————————————————–Microsoft Access 1.01.0Microsoft Access 1.11.1Microsoft Access 2.02.0Microsoft Access 2.02.5 with Microsoft Access Service PackMicrosoft Access 7.03.0Microsoft Access 973.5 with Office 97Microsoft Access 97 SR13.5 with Office 97SR1Visual Basic 3.01.1Visual Basic 3.02.0 with Visual Basic CompatibilityLayerVisual Basic 3.02.5 with Microsoft Access Service PackVisual Basic 4.0 16-bit2.5Visual Basic 4.0 32-bit3.0Visual Basic 5.0 32-bit3.0Visual Basic 5.0 32-bit3.5Visual C++ 4.X3.0Visual C++ 5.03.5Jet 3.51 (web download)3.51 (Latest, 3.5 Binary compatible)
Compatibility Among VersionsWith each new version of Microsoft Jet, enhancements in functionality andchanges to the structure of the database file cause problems with backwardcompatibility. Wherever possible, efforts have been made to ensure an easymigration path among versions. However, incompatibilities do exist. Thefollowing table illustrates how you can use database files and objectsamong different versions of Microsoft Jet.

Jet Version——————————–1.01.12.02.53.03.5———————————————-MDB Version———–1.0YYYYYY1.1NYYYYY2.0NNYYYY3.0NNNNYY
A “Y” indicates that you can use the database without conversion; “N”indicates that you cannot use or convert the database. With DAO code, youcan open any version of any database up to the same version of MicrosoftJet. Microsoft Access is an exception to this rule because it can open onlythose databases with the same version as itself. However, it can link totables with the same or earlier version. In other words, if you upgrade toMicrosoft Jet 3.0, you will still be able to read version 2.x databases.
There is no version 2.5 or 3.5 of an .mdb file (just 2.0 and 3.0), whichare common to the x.0 and x.5 versions of Jet.
Jet 2.0 and Jet 2.5 use identical database formats in every aspect. Jet 2.0can read databases created with Jet 2.5.
Microsoft Jet 3.5 databases have the same structure as Jet 3.0. MicrosoftJet 3.0 can read data from Microsoft Jet 3.5 tables. The main limitationhere is that Microsoft Jet 3.5 may support additional properties on thedatabase object that aren’t recognized or taken advantage of by MicrosoftJet 3.0, but there aren’t any data incompatibilities.
Notice that Visual Basic 3.0 is capable of using three different versionsof Jet each requiring a separate set of dynamic link libraries (DLLs). Thiscan cause problems when your Visual Basic application expects to use Jet2.0 for example, and then you install another Visual Basic applicationusing an earlier version of Jet on the same system that replaces some ofthe version 2.0 DLLs with version 1.1. Typically the problem DLL in thissituation is Vbdb300.dll because it determines which version of the Jetengine will be used.
The following table should help you solve any version conflicts, and helpyou identify the version of Jet you are using. You may use the Wps.exeutility shipped with Visual Basic to find out which version of Jet youcurrently have loaded in memory. Wps.exe is located in the \VB\CDKdirectory of Visual Basic 3.0 Professional, and in \TOOLS\PSS directory ofthe Visual Basic 4.0 CD. Pay special attention to the version informationobtained from File Manager (File, Properties) in Visual Basic 3.0, andMicrosoft System Info. in Visual Basic 4.0 32-bit.
The following files are required by Visual Basic to use the Jet DatabaseEngine:

Jet VersionFileVersionDescription———————————————————————1.1VBDB300.DLL3.00.0528VB/JET supportMSAES110.DLL1.10.0000Expression servicesMSAJT110.DLL1.10.0001Jet 1.1 engineXBS110.DLL1.10.0002External xBASE ISAMBTRV110.DLL1.10.0000External Btrieve ISAMPDX110.DLL1.10.0000External Paradox ISAM2.0 (comlyr)VBDB300.DLL3.00.0529VB/JET supportMSAJT112.DLL1.99.1605Jet 2.x comp. loaderMSAJT200.DLL2.00.0000Jet 2.0 engineXBS200.DLL2.00.0000External xBASE ISAMBTRV200.DLL2.00.0000External Btrieve ISAMPDX200.DLL2.00.0000External Paradox ISAM2.5 (accsvc)VBDB300.DLL3.00.0529VB/JET supportMSAJT112.DLL1.99.1605Jet 2.x comp loaderMSAJT200.DLL2.50.1606Jet 2.5 engineMSJETERR.DLL2.50.1108Error servicesMSJETINT.DLL2.50.1108InternationalXBS200.DLL2.50.1108External xBASE ISAMBTRV200.DLL2.50.1108External Btrieve ISAMPDX200.DLL2.50.1108External Paradox ISAM2.5 (VB4 16)VBDB16.DLL4.00.2422VB/JET supportMSAJT200.DLL2.50.1606Jet 2.5 engineMSJETERR.DLL2.50.1111Error servicesMSJETINT.DLL2.50.1111InternationalXBS200.DLL2.50.1117External xBASE ISAMBTRV200.DLL2.50.1117External Btrieve ISAMPDX200.DLL2.50.1117External Paradox ISAMMSXL2016.DLL2.50.1117External Excel ISAMMSTX2016.DLL2.50.1117External Text ISAM3.0MSJT3032.DLL3.0.0.2118Jet 3.0 engineMSJINT32.DLL3.0.0.2118InternationalMSJTER32.DLL3.0.0.2118Error servicesMSXL3032.DLL3.0.0.2001External Excel ISAMMSRD2X32.DLL3.0.0.2118External Jet 2.0 ISAMMSLT3032.DLL3.0.0.2008External Lotus ISAMMSPX3032.DLL3.0.0.2001External Paradox ISAMMSXB3032.DLL3.0.0.2008External xBASE ISAMMSTX3032.DLL3.0.0.2008External Text ISAM
With Jet 3.5x, there have been multiple releases. The following tableindicates which version of Jet applies to a given product:

Access 97Access 97aFileNameOffice 97VB5Office 97aJet 3.51——————————————————–MSEXCL35.DLL3.50.3428.03.50.3602.53.50.3907.0n/aMSJET35.DLL3.50.3428.03.50.3602.43.50.3907.53.51.0623.4MSJINT35.DLL3.50.3428.03.50.3602.53.50.3907.0n/aMSJTER35.DLL3.50.3428.03.50.3602.03.50.3907.0n/aMSLTUS35.DLLn/a3.50.3602.5n/an/aMSPDOX35.DLLn/a3.50.3602.0n/an/aMSRD2X35.DLL3.50.3428.03.50.3602.03.50.3907.0n/aMSREPL35.DLL3.50.3428.03.50.3602.03.50.3907.13.51.0623.0MSTEXT35.DLL3.50.3428.03.50.3602.03.50.3907.0n/aMSXBSE35.DLL3.50.3428.03.50.3602.03.50.3907.0n/aVBAJET32.DLL3.0.0.69085.0.0.71223.0.0.6908n/aVBAR332.DLL3.0.0.69083.0.0.69083.0.0.6908n/a