hmm in that case they are probably empty then
Though hideen files might not be able to be found, which could be stored in these folders. One way to find out is to open one you think is blank and go to Tools, Folder Options, adn then under the View tab, make it possible to see hidden files, and press okay. Do any appear?
if not, you can be pretty sure its blank
I would try this with about 10 of them to see if any are different.
I hope this helps