Lion Mail: Use account passwords
You can choose to have Mail ask you for your password each time you check messages, depending on your security needs.
- Choose Mail > Preferences and click Accounts.
- Select an account, and then click Account Information.
- Use the Password field to indicate how you want to use your password:
To check messages without first having to provide your password, enter your password.
To be asked to provide your password each time you check messages, make sure the Password field is blank.
Mail automatically stores your password in your Mac OS X keychain. If your keychain is locked and Mail can’t access your password, it asks you to enter your keychain password whenever it needs to access your Mail password.