Oracle : Ошибка ORA-12516

"TNS:listener could not find available handler with matching protocol stack"
*Cause: None of the known and available service handlers for the given
SERVICE_NAME support the client's protocol stack: transport, session,
and presentation protocols.
*Action: 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

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