How to convert OST to PST efficiently
Take help from CloudMigration OST to PST Converter. It is the most reliable and effective method to convert Outlook OST data into numerous other file formats and email clients. With the help of this utility, you can select specific emails that you want to transfer and you can also remove duplicate emails from the conversion. It is very easy to use and ensures proper security to your data. You can try out its free demo version and check its functionality.
Read More - https://www.cloudemailmigration.com/ost-to-pst-converter.php
Somit Vishwakarma commented
Try SysBud OST to PST converter tool: http://www.sysbud.com/ost-to-pst.html