I have run a test again and have included the text from the spool and a screen shot showing that the error message is being displayed in the message window as expected. In this case I am running a query that I expect to fail because the there is no object in my schema with that name. Also I am logged into the database as a user with a DBA role.
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-- Timestamp: 08:49:16.333
Connect: user@database
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-- Session: user@database
-- Timestamp: 08:49:17.257
begin sys.dbms_application_info.set_module('TOAD background query session', '00000000020A4CD0,000000000F92A1C0,0000000017D225C0'); end;
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-- Session: user@database
-- Timestamp: 08:49:17.348
BEGIN SYS.DBMS_OUTPUT.ENABLE(buffer_size => NULL); END;
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-- Session: user@database
-- Timestamp: 08:49:17.423
BEGIN SYS.DBMS_OUTPUT.ENABLE(buffer_size => NULL); END;
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-- Session: user@database
-- Timestamp: 08:49:17.873
select * from test
Error: ORA-00942: table or view does not exist
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-- Session: user@database
-- Timestamp: 08:49:17.969
select * from test;
Error: ORA-00942: table or view does not exist