Cause
The session ID specified in an ALTER SYSTEM KILL SESSION command was not a user session (for example, recursive, etc.).
The session ID specified in an ALTER SYSTEM KILL SESSION command was not a user session (for example, recursive, etc.).
Retry with a user session ID.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e0.htm
https://community.oracle.com/message/11010067
https://community.oracle.com/message/9273960
https://community.oracle.com/message/3421335
https://community.oracle.com/message/2136808
https://community.oracle.com/message/808658
https://community.oracle.com/message/9446075
https://community.oracle.com/message/2025568
https://community.oracle.com/message/1193289
https://community.oracle.com/message/2587467
https://community.oracle.com/message/4497062
https://community.oracle.com/message/1117811
https://community.oracle.com/message/4122490
https://community.oracle.com/message/1228927
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