Why does the ORA-28547 error occur?

Question

Oracle

Hello toasters!
Little experience in SQL. With Oracle so in general for the first time faced.
The question is this: when creating a connection to the Oracle database in Navicat, an ORA-28547 error occurs during the connection
. I'll never know what to do with it.

Answer 1

Well, in general, this error means that it is not possible to connect to the server using the parameters specified in tnsnames.
what does tnsping show?