Open and read an archive
Choose File > Open, select an MBOX file or Apple Mail mailbox package, and wait for the first message rows to appear. Select a row to read it. The status bar reports how much of the archive is available while larger archives continue opening in the background.
Find a message
Choose Basic Search from Search Level for fast header and label search, or Content Search when you also need to find words inside message bodies. Type your query in the toolbar search field.
Take messages elsewhere
Select one or more messages and use the File menu to export EML files, extract attachments, print, or restore mail to IMAP. Open Mailbox Utilities to perform the same kinds of work across the complete archive.