Oracle Error Message
ORA-12639: Authentication service negotiation failed
Reason for the Error
No match was found between the types of authentication services that the client supports and those that the server is using.
Solution
Possible solutions:
1. Change the entry in sqlnet.ora that determines which services are to be used.
2. Relink the client with at least one of the authentication service adapters that the server supports.
3. Relink the server with at least one of the authentication service adapters that the client supports.
4. Disable authentication on both the client and server.
