MDAC Test Failed - Tips & Hints

Background:

StudioLine requires working Microsoft Data Access Components (MDAC), version 2.5 or higher, including a working Jet engine, version 4.0 or higher. Various Microsoft operating systems and applications from Microsoft and other vendors include or install different versions of MDAC and Jet. 

Potential Problems:

Normally there shouldn't be any problems, since newer versions of MDAC and Jet always include the capabilities of older versions and proper setups don't install older versions on top of newer versions.

Unfortunately, not all installation programs are "proper" and, some installation programs may completely or partially overwrite a newer MDAC or Jet with an older version.  Indeed, Microsoft’s own MDAC installations earlier than version 2.5 may cause this problem.   This mix of conflicting versions leads to massive problems when trying to use MDAC or Jet.

How StudioLine Deals With MDAC and Jet:

StudioLine setup checks whether MDAC and Jet are available and working. Depending on the versions of MDAC and Jet found and depending on the operating system version used, the following outcomes are possible:

•	MDAC and Jet are new enough and are working properly (no action is required)
•	MDAC and/or Jet are unavailable or not new enough (can happen when running Windows 98 or NT4). StudioLine will install MDAC 2.52 or Jet 4.0 SP3, respectively.
•	MDAC and Jet are new enough but are not working. It now depends on the operating system whether StudioLine will install MDAC 2.52 and/or Jet 4.0 SP3 or whether doing this doesn't promise success. Windows 2000 and Windows XP already contain current versions of MDAC and Jet and prevent the installation of the MDAC versions distributed with StudioLine.
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•	Recommendations For Damaged Systems:
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•	When StudioLine setup detects a corrupted MDAC or Jet environment, it is unable to resolve the problem automatically. Instead, we recommend that you consider the following steps:
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•	Install the newest version of MDAC and Jet. You will find these on http://www.microsoft.com/data or possibly by selecting "Windows Update" in the start menu. Unfortunately, this will only work if there is a newer version available than the one you've already installed. As of the date of this writing (July 2003), this is not yet the case for Windows/XP. You may need to perform a “repair install” to Windows/XP as described in the Microsoft Knowledge Base article 315341.  http://support.microsoft.com/?id=315341
•	Use the "Component Checker" from Microsoft (found on http://www.microsoft.com/data) to check your MDAC/Jet installation. Especially review the column "FileVersion" found under "COM Details", the versions listed here should be consistent for all components.
•	Under Windows 2000, "Component Checker" might be able to completely uninstall MDAC and replace it with a fresh installation. Please consult the documentation of Component Checker or contact Microsoft, if you want to try this.

On Windows/XP, according to Microsoft there is no other way to repair a defective MDAC/Jet, except by reinstalling your operating system. Please contact Microsoft with any questions. When reinstalling your operating system you should take care not to install any older applications. Otherwise, they might again overwrite the current MDAC or Jet with an older version, reintroducing the original problem. It would not matter, whether StudioLine or the defective applications are installed first - any installation of the defective application will prevent StudioLine from working.

Applications known to overwrite MDAC or Jet with older versions:

IBM Client Access Express AS/400 Terminal Emulation Version 4.5: On (at least) German Windows versions, this program installs MDAC 1.5 on top of any existing version. MDAC 1.5 setup was not correctly localized and thus doesn't find the available MDAC installation (e.g., version 2.7 on Windows XP). More current versions of Client Access Express (at least 5.1 and higher) work correctly and don't cause problems. Note: A system that once had version 4.5 installed will not be repaired, simply by updating to version 5.1.

Do-It-Yourself WILLS & TRUSTS™ © 2000 Expert Software, Inc.: installs MDAC 2.1 regardless of which version is already present. According to Microsoft, systems using Windows XP will require a "repair install" as described above after this program is installed.