I recommend you to use the MCT Outlook PST Converter tool to convert PST to EML, MBOX, MSG, HTML, EMLX, MHTML, MBOX, OST, CSV, and other File Formats. This utility is compatible with all versions of MS Outlook and Windows-based operating systems. It provides an interactive interface to its technical and non-technical users. Download the demo version to back up the first 50 emails to any selected format.