If possible, you can contact the website admin and ask them to grant you access to the problematic file.
In other words, there’s nothing you can do to iron this error out. Most likely, only a limited number of users have the necessary permissions to download that file. The error indicates the admin or website owner has restricted access to the file you’re trying to download. The bad news is that you can’t really do much to fix this issue. Why Does Google Say the Download Needs Authorization?
