[macfly]

have a question for those experienced with security on os x. if i share a computer with someone and they have the root user account is it possible for them to read my email?
i tried setting up another account on my powerbook with its own email. if i log in as root and go to that users folder and open their mail box inbox nothing happens except a strange mail form shows up. the point is i cant see whats in the inbox, only deleted mail or sent mail files. why wouldnt the inbox mail show up? im not so savvy when it comes to this and cant figure out why my inbox mail wouldnt be available but sent / deleted would?
anyone have a clue and will the root user be able to examine contents of my inbox?

[Big Mac]

Root overrides all access privileges, so it is possible to read anything on the system. But root cannot impersonate another user and run as if it is that user, so it is not as simple as opening those mailbox files with Mail as root. I imagine the mailbox files could be copied over to root's Mail folder and then be read that way, however. Otherwise, the root user would have to extract the data from the files manually.

If you're concerned about the possibility of root reading your files, you may want to use FileVault (System Preferences: Security). Be sure to read up on it though - there are some issues with FileVault and it's a good idea to know how to handle those issues in the event that they pop up.

[cpac]

2 points:

(1) Yes - a true "root" user can do pretty much anything on the system.

(2) Don't create a "root" user - there's no need, and it can only lead to damaging your machine. If by "root user" you actually meant "Administrative user" then it is more difficult for them to read your email.