by Emma Richardson.
So this is just happening when you manually create the backups? Have you checked the permissions settings on your account? This has to be a permissions issue.
What happens when you put another file in your private files folder - a word document for example. Can you open it?
The mbz files must be real files - you already stated that they are using up hard drive space. They are probably just hidden in the mass of folders that the Moodle file system creates.