Had a similar problem with a production server. You can try this:
1. Upload this code as test.php on your production server. Replace https://www.example.com/ with your site.
<?php
$mysite = "https://www.example.com/";
error_reporting(E_ALL & ~E_NOTICE);
ini_set('display_errors', TRUE);
$html = file_get_contents($mysite);
if ($html !== false) {
echo htmlentities($html);
} else {
echo "No data from $mysite";
}
?>
2. Open https://www.example.com/test.php in your browser. Replace https://www.example.com/ with your site.
Does something like this appear?
Warning: file_get_contents(https://www.example.com/): failed to open stream: Connection refused in /...
No data from https://www.example.com/
3. If yes, add this line define('ALTERNATE_WP_CRON', true); in wp-config.php, then manually start the job in backend.
4. Now BackWPup probably works, but only manually!
It’s a problem of production servers behind firewalls, load balancers or similar, they can’t access the own site via http.
