I have been using Oracle12c client to connect to an Oracle11g database in a remote server for about one month, it wasn't giving me any problems until this week, when I started getting the error:
The Network Adapter could not establish the connection Provider Code 17002
First I used Oracle Sql Developer to design the tables of the database, and a week after that I started to develop an app with Visual Studio 2013, where I used the native adapter and the library
Oracle.DataBase.Client as part of the Visual Studio Integrated Tools that oracle provide to work with their databases.
I would like to know if the errors could be because the client is 12c and the database is 11g or if this question doesn't matter and another thing can be happening.