Hitting "Error 57: Error loading message shared library" can be a real momentum-killer when you're just trying to run a quick query. This error is a bit of a "catch-all" that usually pops up right at startup because SQL*Plus can’t find or access the core files it needs to talk to you. Oracle Forums
After installing Oracle Client or attempting to run sqlplus from the command line, you see the following error: Hitting "Error 57: Error loading message shared library"
This error often surfaces when the system or specific user session lacks enough RAM to load the Oracle client libraries. Likely root causes This is the most frequent culprit
Likely root causes
This is the most frequent culprit. SQL*Plus needs to know exactly where its "home" and libraries live. On Linux/Unix ORACLE_HOME is set and LD_LIBRARY_PATH includes the $ORACLE_HOME/lib directory. Hitting "Error 57: Error loading message shared library"