ORA-28040: No matching authentication protocol altink 03/28/24 10:46 PM
Hi

When I try to connect with an Oracle 11g R2 Classic Client to an Oracle 19c DB, with both:
PL/SQL Developer 11.0.4
DOA Runtime (Design-time - Delphi TOracleSession) 4.1.3.5 - Delphi 10.1 Berlin

I get error ORA-28040: No matching authentication protocol
(which can be fixed DB-side by adding SQLNET.ALLOWED_LOGON_VERSION=9 on sqlnet.ora - but this is not the point).

When on Run-Time from my app.exe, made with DOA and Delphi same version, I am trying to connect to an Oracle same 19c DB,
I do not have ORA-28040, but do logon successfully.

What I have noticed is that in the Full Oracle Client 11g there is no oraociei11.dll.
But it is on the same dir of my app.exe, as I got it together with oci.dll from Oracle 11g Instant Client.
If I remove oraociei11.dll from the folder of app.exe, I get the same behavior: ORA-28040

I wander what is this all about

best regards
Altin
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