Cause
The specified user does not exist in the database.
The specified user does not exist in the database.
Correct the user name or create the user.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12400.htm
https://community.oracle.com/message/1844370
https://community.oracle.com/message/1846960
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