I had 2 shares on my MyBook. One called “Matt” and one called “MattMusic”. The “Matt” share was empty and the “MattMusic” share contained 20GB of music. In Dashboard it showed the empty share having the 20GB in it and the Share with 20GB in it to be empty. I renamed “MattMusic” to a new name and the used space began reporting correctly. I believe this to prove there is a bug in how Dashboard reports used space when shares start with the same string. Hope this helps anyone else having this issue.
Thank you for sharing. I have to try this.