Oracle Error Message
ORA-12526: TNS:listener: all appropriate instances are in restricted mode
Reason for the Error
Database instances supporting the service requested by the client were in restricted mode. The Listener does not allow connections to instances in restricted mode. This condition may be temporary, such as during periods when database administration is performed.
Solution
Attempt the connection again. If error persists, then contact the database administrator to change the mode of the instance, if appropriate.