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Troubleshooting Guide for TNS-12535 or ORA-12535 or ORA-12170 Errors (Doc ID 119706.1)

Last updated on AUGUST 16, 2023

Applies to:

Oracle Net Services - Version and later
Advanced Networking Option - Version to [Release 11.2]
Oracle Database - Enterprise Edition - Version and later
Oracle Database - Standard Edition - Version to [Release 19]
Oracle Cloud Infrastructure - Database Service - Version N/A to N/A [Release 1.0]
Information in this document applies to any platform.


This bulletin is designed to assist in determining what steps to take to troubleshoot and correct ORA-12535/TNS-12535 errors.

This document is based on reported errors and fixes. Where possible, the note numbers are included as a cross reference to reduce duplication. It also includes some information on why the error may have occurred as well as why the fix would work.


This is intended to assist all levels of engineers and customers and is in addition to any troubleshooting guides written specifically in Oracle Docs.


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