Handy Software Lab Products Knowledge Base

What is MDAC?

The Microsoft Data Access Components (MDAC) are a standard database interface for Windows.? MDAC is already included as part of Windows 98, Windows 2000, Windows ME, and Windows XP.? Some early Windows 98 OEM systems shipped without MDAC, however.? MDAC is also already installed on your system if you have Internet Explorer 5.0 (or higher) or Microsoft Office.? MDAC is FREE and is fully supported by Microsoft on all versions of Windows.

The Print Logger? Software require MDAC version 2.5 or higher, with MDAC 2.8? recommended.? Windows 2000 ships with version 2.5, and Windows XP ships with version 2.7.? If you have a Windows 95, 98 or Windows NT system, installing version 2.5 or higher is required.? While older versions of MDAC may work, they may be very slow or have memory leaks.? For best performance, you should install MDAC 2.8 on all versions of Windows.

If your system does not already have MDAC installed, you need to download it and install it according to the instructions given here.? There is no way to run the application without MDAC.?

Microsoft has thoroughly tested MDAC.? However, since this software becomes part of your operating system, there might be some very old systems that have trouble with MDAC.? Handy Software Lab is not responsible for any damage to your system or data loss caused by MDAC.? Because MDAC is system software, there is no way to uninstall MDAC without reformatting your hard disk and reinstalling Windows.? However, as scary as that sounds, problems with MDAC are very rare.? If you are running a database server on your computer, such as SQL Server, Oracle, Sybase, etc, consult with your system administrator before updating the MDAC software on your computer to be sure it's compatible with the database server you are using.

What is JET OLEDB?

MDAC provides a standard database interface for Windows.? The actual database engine used by software products is the JET 4.0 Database engine (or JET OLEDB engine).? The JET 4.0 engine is the database engine used in Microsoft Access 2000 (part of Microsoft Office) and was chosen because it is FREE and is already installed on most versions of Windows.

However, starting with MDAC v2.6, Microsoft stopped including the JET database engine with the MDAC distribution.? So, some systems with MDAC do not have the latest JET database engine files.? Also, older JET database files can cause databases to be be large and slow.? If you are having trouble with slow database operations, be sure to install the latest JET files given below.? The latest version of the Jet 4.0 engine is SP8.

Checking your MDAC version

To see what version of MDAC you are using, or to check your MDAC installation for compatibility or corruption, you can download the MDAC Component Checker application.? This is a Microsoft application written to determine if your MDAC installation has any problems.

?Download MDAC Component Checker from Microsoft

This version of the Component Checker has a dependency on MSXML2.dll. Users who do not have this dll on their machine will be prompted to visit www.microsoft.com/downloads to install MSXML 3.0 SP4 on their machines.

Compacting and repairing databases

Microsoft provides a utility for compacting and repairing JET databases.? If your database has become corrupted, or if a older version of MDAC caused your database to be large and slow, you can use this utility to fix your database and improve performance.

?Download Jet Database Compact and Repair Utility from Microsoft

Installing MDAC and JET OLEDB

For the greatest performance and stability, it is recommended that you install the latest version of MDAC and JET to your computer.? Unfortunately, Microsoft doesn't make this easy, and it will be a multi-step download and install process that depends upon the version of Windows you are using.

If you have any trouble with MDAC on your system, you need to contact Microsoft for assistance.? For more information on MDAC, visit the Microsoft MDAC site.

NOTE: All of the installation files provided on this site are for ENGLISH language users.? If you require installation for non-ENGLISH versions of Windows, go to the Microsoft MDAC site and follow the instructions given there.

Windows NT Installation

Note: You may be required to install the latest service pack for Windows NT before you can install MDAC or JET 4.0.? The latest service pack for Windows NT 4.0 is SP6a and can be found on the Microsoft Windows NT Update site.

Step 1:

Download and install MDAC 2.8.? Earlier versions can cause performance problems or memory leaks.??

?Download MDAC 2.8 from Microsoft
(mdac_typ.exe, 5427 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.

?

Step 2:

Download and install JET 4.0 SP8 OLEDB.??

?Download JET 4.0 SP8 OLEDB for Windows NT from Microsoft
(Jet40SP8_9xNT.exe, 3782 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.

Windows 2000 Installation

Note: You may be required to install the latest service pack for Windows 2000 before you can install MDAC or JET 4.0.? Jet 4.0 specifically won't install unless you at least have Win2000 SP1.

To apply the latest critical patches and updates to your version of Windows, to to the Windows Update Site at Microsoft.? For both performance and security reasons, you should be sure you are always running the latest critical patches and updates for Windows.

Step 1:

Download and install MDAC 2.8.? Earlier versions can cause performance problems or memory links.??

?Download MDAC 2.8 from Microsoft
(mdac_typ.exe, 5427 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.

?

Step 2:

Download and install JET 4.0 SP8 OLEDB.??

?Download JET 4.0 SP8 OLEDB for Windows 2000 from Microsoft
(Jet40SP8_W2K.exe, 2894 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.

Windows XP Installation

Note: You MUST install the latest service pack for Windows XP before you can install MDAC or JET 4.0.??

To apply the latest critical patches and updates to your version of Windows, to to the Windows Update Site at Microsoft.? For both performance and security reasons, you should be sure you are always running the latest critical patches and updates for Windows.

Step 1:

Download and install MDAC 2.8.? Earlier versions can cause performance problems or memory links.??

?Download MDAC 2.8 from Microsoft
(mdac_typ.exe, 5427 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.

?

Step 2:

Download and install JET 4.0 SP8 OLEDB.? Earlier versions can cause performance problems or memory leaks.??

?Download JET 4.0 SP8 OLEDB for Windows XP from Microsoft
(Jet40SP8_WXP.exe, 2893 KB)

Follow the Microsoft instructions for installing and reboot your computer when you are done.