I created an application user appladm on UNIX to be able to access oracle. This user is not the owner of oracle. The user belong sto the dba group. I have set ORACLE_HOME, ORACLE_SID and all necessary variables. However start sqlplus on UNIX where oracle is installed. I enter the user name and password. I get the error ORACLE not available. The oracle owner goes in without any problems. What could the problem be.