You can easily export OST files to PST without facing any problem by using the DataVare OST To PST Converter Expert. It convert the entire data from Outlook OST files like - emails, contacts, calendars, notes, tasks, journals, etc, into PST file format. It support all editions of Outlook such as - 2021, 2019, 2016, 2013, 2010, etc. Datavare has also various software regarding OST data files conversions - like OST To MSG Converter, OST to EML Converter, OST to MBOX Converter and many more.

For more info you can visit it's official websites.