How can users ensure that the XAMPP server is running properly before testing PHP files?

To ensure that the XAMPP server is running properly before testing PHP files, users can check the XAMPP control panel to see if Apache and MySQL services are running. If they are not running, users can start the services by clicking on the "Start" button next to each service. Additionally, users can access the localhost URL in a web browser to see if the XAMPP dashboard is displayed, indicating that the server is running.

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// No PHP code snippet needed for this explanation.