BadImageFormatException is raised when attempting to load the Oracle client library. This problem occurs if you are running in 64-bit mode with the 32-bit Oracle client component installed. (encountered this problem on-line check down to save it)

When one is running on a 64-bit platform. NET application attempts to invoke a DLL that does not support 64-bit execution, this exception occurs. If the application is generated in an unspecified platform (for example, "any CPU"), it will run in the operating system-based 64-bit mode, which can cause this problem. To solve this problem, you can either make the application run in 32-bit mode by specifying to compile for the X86 solution platform, or make the program run on a 64-bit operating system-based WOW64 subsystem and license 32-bit DLLs.

1. Click on the solution you want to run--right----properties, select Build---platform, and change to x86. (both vs2008 and vs2010 are suitable)