Cause
An attempt was made to set SCAN_INSTANCES or CACHE_INSTANCES using the ALTER SYSTEM command to a value larger than the number of available instances.
An attempt was made to set SCAN_INSTANCES or CACHE_INSTANCES using the ALTER SYSTEM command to a value larger than the number of available instances.
See the accompanying message for the current allowable maximum value, or set SCAN_INSTANCES / CACHE_INSTANCES to ALL.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
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