Important: Jet OLEDB 4.0 is an older data access provider included with Microsoft Data Access Components (MDAC) and historically shipped with Windows and Office. It is not provided separately as a modern Microsoft download for newer Windows versions; on 64-bit systems Microsoft Jet 4.0 is unsupported for 64-bit processes. For modern development use Microsoft Access Database Engine (ACE) or other supported providers.
Supports newer Access ( .accdb ) and Excel ( .xlsx ) formats.
If you are seeing an error like "The 'Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine" , it typically means you are trying to run a 32-bit driver in a 64-bit environment. 1. Use the 32-bit Compatibility Mode (WOW64)
You typically do not need to download the provider manually , as it has been a built-in component of the Windows operating system for many years. download microsoft jet oledb 4.0
If you are on a 64-bit Windows 10/11 system, Recommended Approach for Modern Systems
: The Jet OLEDB 4.0 provider was never released as a 64-bit component Stack Overflow Windows Built-in : It is already present in your system's C:\Windows\SysWOW64\ msjet40.dll on 64-bit Windows systems Stack Overflow Deprecated : Microsoft recommends using newer alternatives like Microsoft SQL Server Express for modern development Microsoft Community Hub How to Fix "Provider Not Registered" Errors
While the engine itself ships with Windows, Microsoft did release to provide maintenance fixes and security updates. The most recent of these is Jet 4.0 Service Pack 8 (SP8) , which represents the final update for the Jet Database Engine. Important: Jet OLEDB 4
If you do not own the source code of the app you are trying to run, you have two options:
Security patches for vulnerabilities within WDAC and JET components are routinely deployed via Windows Update. Ensure your hosting servers and client machines are patched.
Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\mydatabase.accdb;Persist Security Info=False; Use code with caution. To help find the right solution, please let me know: Supports newer Access (
You cannot use Jet 4.0 directly. You must download the Microsoft Access Database Engine 2016 Redistributable (64-bit) or newer and update your connection string to use the ACE provider. The Critical Shift: Jet vs. ACE
If you cannot recompile, run your .exe file within the context of a 32-bit environment. 4. Modern Alternative: Microsoft ACE OLEDB
Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\mydatabase.mdb;User Id=admin;Password=; Use code with caution. Connecting to Microsoft Excel (.xls)