In a new installation, we must configure the embedded PL/SQL gateway by running the configuration script apex_epg_config.sql. Then, we must unlock the ANONYMOUS account.
1- Change your working directory to the apex directory where Start SQL*Plus and connect to the database where Oracle Application Express is installed as SYS specifying the SYSDBA role. Run apex_epg_config.sql passing the file system path to the base directory where the Oracle Application Express software was unzipped. For example if your APEX directory is /u01/app/apex then you must pass /u01/app as file system path. Otherwise you will receive an error.
2- Then enter the following statement to unlock the ANONYMOUS account:
ALTER USER ANONYMOUS ACCOUNT UNLOCK;
3- The embedded PL/SQL gateway runs in the Oracle XML DB HTTP server in the Oracle database. We must set connection port for it. Usually this port is 8080.
Connect to the Oracle as SYSDBA and run the following command to set HTTP port.