Use Email Archiver Pro to create a file of all your emails, or just a few folders.
Email Archiver Pro works with Apple Mail for OS X, storing your emails as PDF files. It makes them compatible anywhere can open a PDF, not just Mail. The e – mails are stored hierarchically in the same way that your email is organized into Mail.app. The archive email makes no changes to your mail folders. Just scan your thousands of emails and creates a PDF for each. PDF files created with the full email header embedded in the PDF search purposes.
In addition, all attachments that are displayed online, including photos, etc. They are shown in the PDF. All emails with attachments have a folder with the same name, including attachments next to the PDF. PDF use the subject line and the message ID to create a unique and readable name for the file. Subsequent scans email Archiver only add new emails and, therefore, work faster.