On Fri, Feb 13, 2009 at 11:50 AM, Branimir Petrovic <BranimirP@xxxxxxxx>wrote: > sqlnet.ora has: > SQLNET.AUTHENTICATION_SERVICES= (NTS) > Try commenting that line out in your sqlnet.ora file. NTS is used for windows OS authentication. I just tried this on a linux server with NTS, and it prevents SYSDBA logons with OS authentication. Jared