The Regain OST to PST Converter is one among the most trusted programs which is designed to convert OST files to PST format in bulk. It enables such users to preview the OST files before conversion in order to maintain the folder structure and guarantee data integrity. It not only exports OST data to PST but also can export that data to Office 365, Live Exchange, Gmail, Yahoo Mail, Hotmail, and more. With it, you can save your emails into multiple EML, MSG, MBOX, PDF, vCard, HTML, and ICS formats. You can also test the free version before investing in this product, which has features like setting file size limitation and is compatible with all versions of Outlook and Windows.