– Check that ORACLE_HOME and PATH are set correctly. Echo $LD_LIBRARY_PATH (Unix) or %PATH% (Windows) to ensure the $ORACLE_HOME/lib directory is included. For Unix, also check LD_PRELOAD or platform-specific variables like SHLIB_PATH (HP-UX) or LIBPATH (AIX).
– Temporarily unset NLS_LANG ( unset NLS_LANG on Unix, set NLS_LANG= on Windows). If SQL*Plus starts successfully, the issue lies in the message file directory. Verify that files like sp1us.msb exist in $ORACLE_HOME/sqlplus/mesg . Sqlplus Error 57 Initializing Sql-plus Error Loading Message
– If libraries are present but the error persists, the binaries may be corrupted. Run relink all from $ORACLE_HOME/bin as the Oracle software owner. This re-creates the executables against the installed libraries. – Check that ORACLE_HOME and PATH are set correctly