Click on any folder, and that will get you into windows explorer.
Then browse to the itunes media folder, right-click > Properties.
The security tab is where you set permissions.
Make sure to check the box for child/subfolder permissions to get changed, as well.
A lot of this stuff you can find on your PC with the built-in windows helps.
Start Menu > Help and type something like "permission" in the search area.
Google is also good, " +windows 7 folder permissions+ " brings up a lot of articles and this one has some screen shots of what you will see (scroll down a little) :
http://www.blogsdna.com/2159/how-to-take-ownership-grant-permissions-to-access-f iles-folder-in-windows-7.htm
