Error: Empty hostname / CNAME list.

@pinkcaddytravelogue

Under the configuration section of the CDN, verify if the HOSTNAME is entered corrently. Also verify that the Authorization Key is correct.

You can review some nice tutorials on how to set it up on:

https://www.wpbeginner.com/plugins/how-to-install-and-setup-w3-total-cache-for-beginners/
https://www.maxcdn.com/one/tutorial/setup-wordpress-with-w3-total-cache/

I am sorry for any delay on this issue, have you managed to test
the settings provided in the URL’s provided by @victormj ? Is everything
working as expected? Also, please make sure to have the plugin updated
to the latest stable version. This last version has been released
about 2 months ago and it brought a lot of improvements
over the CDN connection settings.

If you have any other questions, please feel free to ask.

Thank you for using W3 Total Cache!
Kind regards!
Bogdan S.