If You Need a Software which Convert your OST file to PST file, then here is a tool name Regain OST to PST Converter Where you can Convert your OST file to PST file in just few clicks. Regain OST to PST Converter is programmed with lowest exe file footprint which results in superfast conversion and scanning. After uploading a large file for conversion, it scans them immediately and takes least possible time for conversion of large OST files. This tool Supports Microsoft Outlook 2019, 2016, 2013, 2010, 2007, 2003, 2000, 2002, 98 and 97.
Download this tool free Trial Version here: OST to PST