To convert ost to pst there are many tools available on market but i personally recommend you this OST to PST converter software to convert your ost file data to Outlook PST file, where you can access all mail easily. It extracts all the existing folders like tasks, journals, notes, calendars, contacts, and appointments. It thoroughly scans the OST files and converts them into PST, MSG, EML, RTF, HTML, and PDF formats.
Visit here:- http://www.osttopstconverter-tool.com/
If you are looking for Convert OST to PST then download this tool, this Software will help you to Convert your OST to PST file format
If you are facing this issue and want to find a solution, then I will recommend you to try OST to PST Converter tool this software will help you to migrate emails from OST to PST file extension. You can download this software from here:-https://www.toolsbaer.com/ost-to-pst-conversion/