If you want to convert ost to pst then there are two methods available in which you can try any reliable method that can easily Convert OST file to PST file format. First and free manual method is short of complicated method but by reading this blog you'll be able to use manual method easily.

Second and paid method is use any third party OSt to PST Converter software to Convert OST file to PST along with emails, inbox, outbox, sent-items, deleted-items, drafts, contacts, calendars, notes (to, cc, bcc, subject, date and time).

Visit this blog: Import OST to PST