The best way to convert OST to PST is by using OST to PST Converter Software that restores the OST emails along with mailbox components like emails, tasks, drafts, calendars, and contacts. This tool does not harm the internal data of the OST file and also it maintains the folder hierarchy. You can preserve the meta properties like to, bcc, cc, from, date, and subject. It is compatible with all editions of MS Outlook up to 2019.
Visit here - Convert OST to PST
Visit here - Convert OST to PST