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Oracle Troubleshooting

ORA-12516: TNS:listener could not find available handler with matching protocol stack

Symptom:

The error:

ORA-12516: TNS:listener could not find available handler with matching protocol stack

Causes:

None of the known and available service handlers for the given SERVICE_NAME support the client's protocol stack: transport, session, and presentation protocols.

Remedy:

Check to make sure that the service handlers (e.g. dispatchers) for the given SERVICE_NAME are registered with the listener, are accepting connections, and that they are properly configured to support the desired protocols.

Contributed by: Preetham SP.