Error : Could not load file or assembly 'Oracle.DataAccess' or one of its dependencies.

I ran into this problem today in a ASP.NET application on deployment:

"Exception message: Could not load file or assembly 'Oracle.DataAccess' or one of its dependencies. An attempt was made to load a program with an incorrect format."

Some suggest changing your solution by going into Configuration Manager and set your target platform to 64-bit.  Others suggest enabling 32-bit applications in your AppPool.

Before doing that, make sure that your reference properties for Oracle.DataAccess have NOT been inadvertently changed to "Copy Local = true".  Otherwise, your server will be using your copy and not the one in the GAC.