My application installs for a single user on a Windows machine. Any user may install the application for himself, but the application will save some information common to all users in a separate directory (currently in the subdirectory of the hidden ProgramData folder on Win Vista, 7 and 8). The application will need read and write access to this subdirectory and all of its subdirectories.
What are the minimum access rights, and which user must have them, i.e. do I need to assign read/write access to that subdirectory to each user separately, or is it enough to assign it to one user/group and which one? The application runs on Windows XP, Vista, 7 and 8.