Oracle Database / Connections & Oracle Net
ORA-28040: diagnose client authentication compatibility
An old client may not support the authentication protocol required by the database. Establish both client and database versions before weakening authentication policy.
Environment and inputs: Oracle Database 19c baseline · SQL*Plus-compatible SQL unless RMAN, DGMGRL, ADRCI or a host shell is specified. Check release, patch level, edition and container first.
Start with this diagnostic
Use the stated SQL, RMAN, DGMGRL or host shell and replace sample names with approved targets. DBA and V$ views need authorized catalog access in the correct container. Do not grant broad privileges for an example.
sqlplus -VRead the result
At the affected native client, this prints the SQL*Plus release. For a Java or managed driver, collect that driver's version independently rather than treating this as its version.
Resolve and verify
Compare the actual driver with Oracle's supported compatibility guidance and account password-verifier configuration. Prefer a supported client update coordinated with the application owner.
Operational precautions
Do not lower authentication security globally as a quick fix. Password-verifier changes can require a controlled credential rotation.