The provider is not compatible with the version of Oracle client


I'm trying to use the Oracle ODP.NET 11g ( Instant Client on my project as a Data Provider but when I run the aspx page I get a "The provider is not compatible with the version of Oracle client" error message. Any help would be appreciated.

I've referenced the Data Provider in Visual Studio 2005 and the code behind looks like this:

using Oracle.DataAccess.Client;

OracleConnection oOracleConn = new OracleConnection();
oOracleConn.ConnectionString =
    "Data Source=MyOracleServerName;" +
    "Integrated Security=SSPI";

//Do Something


The error for the page looks like this:

Exception Details: Oracle.DataAccess.Client.OracleException: The provider is not compatible with the version of Oracle client

Source Error: 
Line 21: 
Line 22: 
Line 23:             OracleConnection oOracleConn = new OracleConnection();
Line 24:             oOracleConn.ConnectionString =
Line 25:                 "Data Source=MyOracleServerName;" +

[OracleException (0x80004005): The provider is not compatible with the version of Oracle client]
   Oracle.DataAccess.Client.OracleInit.Initialize() +494
   Oracle.DataAccess.Client.OracleConnection..cctor() +483

Stack Trace: 
[TypeInitializationException: The type initializer for 'Oracle.DataAccess.Client.OracleConnection' threw an exception.]
   Oracle.DataAccess.Client.OracleConnection..ctor() +0
   Boeing.IVX.Web.RoyTesting.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\CE218C\Desktop\IVX.Net\Web\IVX\RoyTesting.aspx.cs:23
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +15
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +33
   System.Web.UI.Control.OnLoad(EventArgs e) +99
   System.Web.UI.Control.LoadRecursive() +47
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1436
11/20/2013 10:17:59 PM

Accepted Answer

I only installed the Oracle Data Provider for .NET 2.0 ( and I did not install the Oracle Instant Client (

I just installed it and the error disappeared!

11/27/2013 3:33:23 PM

I've been looking into this problem further, and you simply need to grab all the appropriate DLL's from the same downloaded version of ODP.Net and put them in the same folder as your Exe file, because ODP.Net is fussy about not mixing version numbers.

I've explained how to do this here: Here's the gist of it though:

  • Download ODP.Net
  • Unzip the file
  • Unzip all the JAR's in it
  • Grab these dll's that were just unzipped:
    • oci.dll (renamed from 'oci.dll.dbl')
    • Oracle.DataAccess.dll
    • oraociicus11.dll
    • OraOps11w.dll
    • orannzsbb11.dll
    • oraocci11.dll
    • ociw32.dll (renamed from 'ociw32.dll.dbl')
  • Put all the DLLs in the same folder as your C# Executable

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