12.2: ORA-28040 is thrown for 11gR2 client - Same client was ok with 12.1
Following an upgrade to 12.2, the ORA-28040 errors might be thrown when an 11gR2 client connects.
The same version 11gR2 client connected successfully to 12.1. The failing Oracle client might be lower than version 11.2.0.3.
The default setting for SQLNET.ALLOWED_LOGON_VERSION_SERVER has changed in version 12.2.
It is now 12.
The setting of 12 will allow clients 11.2.0.3 and newer to connect. Any client below 11.2.0.3 will need the CPUOct2012
PSU applied OR an explicit setting for SQLNET.ALLOWED_LOGON_VERSION_SERVER that is 11 or lower.
See the following 12.2 documentation:
Parameters for the sqlnet.ora File
See the following 12.1 documentation for the same setting:
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