ORA-28040: No matching authentication protocol exception

Here is some text I found at experts-exchange:

Bug 14575666

In 12.1, the default value for the SQLNET.ALLOWED_LOGON_VERSION parameter has been updated to 11. This means that database clients using pre-11g JDBC thin drivers cannot authenticate to 12.1 database servers unless theSQLNET.ALLOWED_LOGON_VERSION parameter is set to the old default of 8.

This will cause a 10.2.0.5 Oracle RAC database creation using DBCA to fail with the ORA-28040: No matching authentication protocol error in 12.1 Oracle ASM and Oracle Grid Infrastructure environments.

Workaround: Set SQLNET.ALLOWED_LOGON_VERSION=8 in the oracle/network/admin/sqlnet.ora file.

I deleted the ojdbc14.jar file and used ojdbc6.jar instead and it worked for me

This except for adding the following to sqlnet.ora

SQLNET.ALLOWED_LOGON_VERSION_CLIENT = 8
SQLNET.ALLOWED_LOGON_VERSION_SERVER = 8

If you get "ORA-01017: invalid username/password; logon denied" error, then you need to re-create your password.

I resolved this issue by using ojdbc8.jar. Oracle 12c is compatible with ojdbc8.jar