eSoftTools OST to PST Converter software is a very popular Outlook OST file conversion tool. It comes with very simple and easy-to-understand interface. Users can easily use it. Its converts Outlook OST files to PST and many other formats such as Gmail, Office 365, Yahoo, MBOX, MSG, EML, HTML, EMLX, vCard, ICS, and Zimbra. The bulk conversion option helps you to convert multiple Outlook OST files at the same time. Try the free demo version of this tool and get 25 mailbox items from each folder.