Cause
Starting this instance would exceed the maximum number of instances allowed for this database. This message occurs only with STARTUP shared and multiple instances.
Starting this instance would exceed the maximum number of instances allowed for this database. This message occurs only with STARTUP shared and multiple instances.
You cannot start more than the lower of a) port-specific limit as to the number of instances b) the number of instances specified at create-database time
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e0.htm
https://community.oracle.com/message/2191950
https://community.oracle.com/message/2356325
https://community.oracle.com/message/9316784
https://community.oracle.com/message/10013525
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