"Not able to connect" could be lots of things. First, what error do you get? Second, what kind of connection, exactly, are you trying to make? Please be more detailed and specify what kind of connection we're talking about. Are you using SSIS ? SSIS, when run in 64-bit mode, can NOT access 32-bit ODBC drivers, so if you need both, then you'll need separate packages or a custom script.