Developing for Windows Server 2003 64 bit on Windows XP 32 bit

Question

I have been developing an ASP.NET application on Windows XP Professional. While promoting to production I have only now found out that the server is 64 bit. I installed Oracle Client 32 bit on the server and cannot connect to Oracle.

I am using the Microsoft Provider for Oracle, and my question is, how do I get an ASP.NET application compiled on a 32 bit machine to connect to Oracle on a Windows Server 2003 64 bit machine?

EDIT:

In response to a comment on my original question, the error I am getting is "Attempt to load Oracle client libraries threw BadImageFormatException. This problem will occur when running in 64 bit mode with the 32 bit Oracle client components installed"

I have uninstalled the 32 bit client and am getting the 64 bit client installed, the problem is that the server is a production server in a DMZ and I have no access to the server myself, so I am trying to anticipate any problems I will have when the 64 bit client is installed and I try to access the ASP.NET application on the server

Answer 1

Another thing to try would be to set the app pool hosting the application to 32-bit mode. http://extended64.com/blogs/rhoffman/archive/2005/05/10/482.aspx

This should allow a 32-bit driver to be loaded.

Answer 2

Straightforward solution : you should install the Oracle client according to the platform (x64 on a x64 machine). The reason is that your .NET application is very likely to be built in AnyCPU configuration, which means it will run as a x64 application on a x64 platform. It then can only load x64 native libraries...

Note that when it comes to Oracle, I like to use Oracle Instant Client :

• You don't have to install anything on the target machines (including dev boxes !).
• You can make sure that your application will run with the specific client you picked (version, x86/x64).
• You could even easily have multiple applications work with different client versions on the same computer.
• As a downside, it adds a significant weight to your application (~19Mb minimum).

Check What is the minimum client footprint required to connect C# to an Oracle database? for more information.

In your particular case, I recommend setting up a Visual Studio project that will work on x86 as well as x64 machines : check my blog post Oracle Instant Client in Visual Studio. Then here is a guidance on how to configure a WiX package for Oracle Instant Client targeting x86 or x64 machines. If you use another deployment strategy, just make sure you ship the correct client according to the target platform.