Cause
The specified directory for the database files was already in use by the Global database name that was provided.
The specified directory for the database files was already in use by the Global database name that was provided.
Specify a different location or go to the previous screen and change the Global database name.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/dbinstaller_errormessages.htm
https://community.oracle.com/message/10823856
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