ORA-28593: agent control utility: command terminated with error
Cause: An error occurred during the processing of the command. There could be several causes. A SET or an UNSET command could have been issued after the agent was started. This is illegal. The user may have attempted to start two agents with the same SID value or the user could have attempted to shutdown an agent that is no longer running
Action: If the user wishes to issue a SET or an UNSET command, he should make sure the agent is shutdown first by issuing the SHUTDOWN command
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