This error suggests a version mismatch between Oracle.DataAccess.dll and the native Oracle Client libraries it depends on, like oci.dll .
Compatibility & risks
Add to app.config :
: Indicates the library targets .NET Framework 4.0 or higher. It will not run natively on applications isolated to .NET Framework 2.0 or 3.5. oracle.dataaccess.dll version 4.112.3.0 download
If you are starting a new project or can refactor, Oracle recommends switching to the Managed Driver Oracle.ManagedDataAccess.dll Oracle Forums
While there is a NuGet package for Oracle.DataAccess.x86.4 , it is a community-maintained package and may still require a local Oracle client to function. Key Technical Specifications Full Version ODAC Release 11.2 Release 4 (11.2.0.3.0) Target .NET Framework .NET Framework 4.0, 4.5, and above Processor Architecture x86 (32-bit) or x64 (64-bit) versions available Primary Dependency Requires Oracle Client (Instant, Runtime, or Full) Installation & Troubleshooting Steps 1. Registration in the GAC
A loose DLL may be 32-bit (x86) when your application requires 64-bit (x64), or vice versa. This error suggests a version mismatch between Oracle
Available in both 32-bit (x86) and 64-bit (x64) versions.
To download and successfully use oracle.dataaccess.dll version 4.112.3.0 , the most reliable method is installing directly from Oracle's archives. This ensures that the DLL is correctly GAC-registered and that all dependencies are installed.
: Aggregator sites are known vectors for malware, adware, and backdoors bundled inside systemic libraries. If you are starting a new project or
Method 1: Using the XCopy Package (Recommended for Deployment)
Here are solutions to some of the most frequent issues developers encounter.
If your architecture allows, the most effective way to eliminate oracle.dataaccess.dll dependency issues is to migrate to Oracle's fully managed driver: Oracle.ManagedDataAccess.dll . Benefits of the Managed Driver
Specifically 32-bit (x86) . If you need a 64-bit version, you must typically look for the newer 11.2.0.4.0 release, as a dedicated 64-bit installer for 11.2.0.3.0 is not standard.