I have a guest account on my computer that my friends sometimes use. It only lets them use like Safari, Pages, and Keynote, which is all my friends would ever need to do on my computer. Anyways, when they're logged into it, they aren't allowed to write files to their USB drives, or delete them. They have read only access basically. Why is this and can I change it? I never really used the managed accounts before thus the reason for all the questions.