Dreamweaver could not securely connect to your server [Branched]

Just because a domain has SSL/TLS certificates, does NOT mean the certificates extend to your server's backend.

You would need to consult your hosting provider about that.

Old fashioned MySQL connections WON'T work with server's running PHP 7 or higher.  On modern servers, you need modern code written in MySQLi (improved) or PDO. 

Below is an example of MySQLi.  Change values in red to your own.  SaveAs test.php and upload to your remote server.  Test it by going to test.php from your browser.

<?php
$con = mysqli_connect("localhost","your_username","your_password","database_name");

// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
else echo "Successfully connected, happy coding!"
?>

<?php phpinfo() ?>

@Renee Pettit - As this post is over a decade old, if you are having an issue, I would recommend starting a new thread.