For a client program to be able to connect to the MySQL server, it must use the proper connection parameters, such as the name of the host where the server is running and the user name and password of your MySQL account.
When the connection to the database cannot be established, the server returns an error message including the MySQL username and host that were used. This information should not be present on a production system.
Make sure the MySQL connection can be established and configure PHP not to display error messages.
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