Cause: An improper command was sent to the Connection Manager or it is not responding. This message is not normally visible to the user.
Action: Verify that the correct addresses are listed in the TNSNAMES.ORA, TNSNET.ORA, and TNSNAV.ORA configuration files. Also check that the Connection Manager is running by using the STATUS command of the Interchange Control Utility. If the error persists, contact Oracle Support Services.
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