E-mail, chat, & VoIP : Help me setup my Outlook

Help me setup my Outlook

I'm looking to setup multiple email accounts using Outlook. There will be multiple people using my machine and while I'm not afraid of any of those people doing anything malicious, I'd still like to have some privacy. I've created a profile and set it so that it doesn't remember my password. But I've noticed when I launch Outlook, that only prevents it from downloading my new messages. Any previous messages are still there for anybody to read. I'm not even sure how I'd switch to another persons profile/identity. What I'd ideally like is a setup where anybody who uses this computer needs to enter a password to access their Outlook account and only then can they view any messages (either new or old). There's gonna only 2 primary users on this machine I think I should point out, so I'm looking for simple answers. Can somebody point me in the right direction?