Oracle connectivity

HI,

    What Oracle software do i need to install on the client to access a server. My front end is Powerbuilder. I installed sql*net and interface for windows. but it does not work.

    Is there any way I can access the server with no oracle files or the most minimun required files. If yes can anyone tell me what those files are.

Any help is greatly appreciated.

                                Thanks
                                       Hider.