ORA-28040 Error with Oracle

Discussion of open issues, suggestions and bugs regarding ADO.NET provider for Oracle
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John Liu
Posts: 61
Joined: Wed 14 Nov 2012 20:58

ORA-28040 Error with Oracle

Post by John Liu » Wed 10 Jan 2018 18:20

We were using dotConnect for Oracle 9.2 to work with Oracle in direct connect mode, everything worked great. We recently upgraded our oracle server to, and then got the following error when trying to connect to the database.
ORA-28040: No matching authentication protocol


Devart Team
Posts: 2106
Joined: Wed 02 Nov 2011 09:44

Re: ORA-28040 Error with Oracle

Post by Pinturiccio » Fri 12 Jan 2018 15:47

Oracle 12c authentication in the Direct mode is supported starting from dotConnect for Oracle 9.2.220. For more information, please refer to https://www.devart.com/dotconnect/oracl ... story.html

There were also a few issues with connections to Oracle 12c server in the Direct mode in several subsequent versions. We recommend you to use the latest version of dotConnect for Oracle.

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