What is the minimum installation on a IIS web server to enable connection from ASP.NET applications to connect to Oracle 11g database through TNSNAMES.ORA?
What version of IIS / ASP.NET are you using?
Oracle .Net Software Downloads
I think the XCopy versions are the smallest.
Oracle.ManagedDataAccess.dll is the smallest. Install the 12c FULL client and register the asp.net stuff on your developer machine.
Deployment requires nothing other than the .NET DLL. It's the cat's meow... Oracle client configurations are a nightmare.
Check out my accepted answer here: https://forums.oracle.com/thread/2586400