How to fix the Oracle error ORA-12658: ANO service required but TNS version is incompatible?

In this post, you’ll learn more about the Oracle ErrorORA-12658: ANO service required but TNS version is incompatible with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-12658: ANO service required but TNS version is incompatible

Reason for the Error ORA-12658: ANO service required but TNS version is incompatible

A client process that is running an earlier version of TNS attempted to connect but the connection failed because the server process required that an ANO service (authentication, encryption, etc.) be used.

How to fix the Error ORA-12658: ANO service required but TNS version is incompatible ?

You can fix this error in Oracle by following the below steps

Relink the calling executable and retry the connection or eliminate the requirement that the service be used on the server side.