If any user looking for the best OST to PST converter tool to convert OST Outlook files to PST. In that situation, I would like to suggest SysInspire OST to PST Converter software. Because it has the facility to convert OST file to many different file formats like PST, HTML, EMLX, MSG, ICS, EML, Office 365, MBOX, vCard, etc. Using this software is very simple as its user interface is very simple and easy to understand. In this software, users get the facility to convert multiple OST files at once. A free demo is available in this software, which you can use before purchasing the software and convert 25 emails from each folder of OST file.