What client is failing to show content?

Note that clients sometimes only show File Types that they're compatible with.

Hi!
Please help me with this:

I enabled MM Library and Server in Media Sharing and in options>shared content I checked all check boxes but all the folders show 0 items. As I can't choose a path for folders that I want to share I don't know why the server doesn't have any content.
(I use version 4.1.18 and Win7)