using (OleDbDataReader reader = command.ExecuteReader())
By design, Microsoft prevents side-by-side installation of both bit versions of the Access Database Engine. The installer checks for existing Office components and blocks installation.
If it exists, the mso.dll registry value. Deleting this specific path pointer stops Microsoft Office from checking and blocking the alternate bitness provider. Summary Connection String Examples download microsoft.ace.oledb.12.0 provider for both 64-bit
If you are developing applications that require both architectures (e.g., a 32-bit app and a 64-bit app), you need a specific installation order to avoid registry conflicts.
The "Microsoft.ACE.OLEDB.12.0" (Access Connectivity Engine OLE DB) is a database driver from Microsoft. Its core function is to facilitate data transfer between non-Microsoft Office applications and popular Office file formats. It allows programs (written in C#, VB.NET, Python, etc.) to read from and write to: using (OleDbDataReader reader = command
The "Microsoft.ACE.OLEDB.12.0" provider is part of the . While older 2010 versions are harder to find on official landing pages, the 2016 Redistributable is the current standard and provides the updated OLEDB 16.0 driver, which often maintains compatibility with 12.0 connection strings.
If you try to double-click the second installer after finishing the first, Microsoft Office will throw a compatibility block error. You can completely bypass this check by forcing a silent/passive command-line installation. Download link for Microsoft.ACE.OLEDB.12.0 Deleting this specific path pointer stops Microsoft Office
The provider is a critical data engine that allows applications to connect to Microsoft Office files, such as Excel spreadsheets ( .xlsx ) and Access databases ( .accdb ). A common headache for developers and system administrators is resolving the infamous error: "The 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine."