This message appears if and only if you are you using the default backup output directory (<path to your site>/administrator/components/com_akeeba/backup or [DEFAULT_OUTPUT]) in the active backup profile. The instructions on the page you linked tell you that you need to create a new backup output directory, ideally outside your web root. Only then will the message disappear.
They also tell you that if you cannot create a new backup output directory you will probably not need to be overly worried because Akeeba Backup itself is placing .htaccess and web.config files in there to prevent direct access. Note that per our documentation, if Akeeba Backup cannot guarantee that the backup output directory is inaccessible over the web it will be automatically appending 16 random characters at the end of the backup archive name to make it far less likely that an attacker can guess the filename and download the backup over the web.
So, to sum it up.
Create a new backup output directory above your site's web root.
Edit each and every backup profile you have and:
- Set the backup output directory to the new folder in the Configuration page.
- Exclude the administrator/components/com_akeeba/backup folder in the Files and Folders Exclusion page.
This will make the message go away and increase the security of your backups.
Nicholas K. Dionysopoulos
Lead Developer and Director
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