I have a notebook and an external hard drive (which houses my music). i am owner of the files in the firewire drive. i created a second user called "stranger" so my sister could still listen to music through airport express. I would like "stranger" to have read-only rights (because i do not want anybody accidentally deleting the music files). with my user "al" -> owner: al, access: read & write; group: stranger, access: read only; others: no access; i clicked "apply to enclosed items" (i guess this meaning all subfolders would follow the permissions stated before); ignore ownership on this volume is deactivated. my initial question is: how can i set permissions throughout the whole external hard drive? i want to have read & write permission and other users should only have read-only permission and/or maybe "no access" permission.