There is no longer an Identities feature in Windows Mail. There was one in
OE, but the password protected Identities were really providing a false
sense of security, as anyone can access anyone's dbx files within a given
User's log on space.
If you want security, then you have to log on as a specific Windows user
now, and then you have your private email space. Another user, such as a
family member, would then have to sign on as a separate Windows user to have
a separate and secure mail store.
The suggestion to require your mail password prompt is only helpful for
downloading new messages, as anyone with access to your Windows user space
now will have access to any messages you have there.
To put it simply, there is no security within Windows Mail. The security of
your messages now is based upon your Windows User logon Identity and your
mail is tied to that.
steve