Error: "Could not load file or assembly 'Oracle.DataAccess, Version=%s, Culture=neutral, PublicKeyToken=%s' or one of its dependencies. An attempt was made to load a program with an incorrect format" (Doc ID 1367695.1)

Last updated on JULY 03, 2017

Applies to:

Oracle Data Provider for .NET - Version 10.2.0.1.0 and later
Microsoft Windows x64 (64-bit) - OS Version: 7
Microsoft Windows x64 (64-bit) - Version: 2008 R2
Microsoft Windows x64 (64-bit)

***Checked for relevance on 03-Jul-2017***

Symptoms

Using Microsoft Visual Studio and building simple C# or VB.NET application using Oracle Data Provider for .NET 64-bit gives during run time following error

"Could not load file or assembly 'Oracle.DataAccess, Version=%s, Culture=neutral, PublicKeyToken=%s' or one of its dependencies. An attempt was made to load a program with an incorrect format."


even if PATH, ORACLE_HOME and GAC_64 contains correct entries and references:

Cause

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