Archived - Mac OS X Mail: How to import email
Mail can import messages from other email applications.
Open Mail, choose Import Mailboxes from the File menu, and follow the instructions that appear.
To see the messages in Mail, look in the mailbox named Imported Messages.
If you don't see your mailboxes in Mail, choose Show Mailboxes from the View menu.
To reorganize imported email, you can create new mailboxes and drag messages from Imported Messages to other mailboxes.
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