string connString = string.Format("Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST={0})(PORT=1521))(CONNECT_DATA=(SERVICE_NAME={1})));user id = {2};password = {3}", IPString, SIDString, SystemUser, SystemPassword);
sysy好像要加 sys as sysdba吧,可先用system的试试
我解决了,用odp.net连接有个DBA Privilege=SYSDBA可以用sys权限登录。