Assign folders in c:\ to terminal server users.

Hii,
  I have in WinServer 2008 R2 SP2, policies applied to users in Terminal Server,
these are very limited to users , which only have access to any remote desktop applications , and can not access anywhere else.
   So far so good , the problem is that some claim application to use a specified folder on the hard disk "c: \ folder_to_read " , ie , the app using that default route and is used to read a file ,






How I can do to change the policy and allow them to examine / or access to that route ?.



Thank you.