Launching LSNRCTL produces an error
EdStevens wrote:

&quot;message not found&quot; invariably means that ORACLE_HOME is not set correctly.  The message file (the file with the text of all of the error messages) is located in relation to ORACLE_HOME. If ORACLE_HOME is not correct, then it can't find the message file, and all errors will cascade to &quot;message not found&quot;.

The question author responded:

I think I solved the problem; the Oracle service TNS Listener was not started. I changed the ORACLE_HOME environment variable to: C:\app\Owner\product\18.0.0\dbhomeXE -  I dropped the &quot;\bin&quot; directory.