Hi,

You can try manual method to such task as given below:-
Open MS Outlook
Go to File Menu and Select "Import and Export Wizard" and press 't'.
Select Export a File option and click Next.
Opt PST and click Next.
Browse and select desired location to save converted PST file.
Hit the Finish Button

OR

You can use a third party Kernel for OST to PST Recovery Tool to convert your OST emails, contacts, calendars, tasks, lists, links, attachments, notes, etc. to Outlook 2016.

Download trial version here:- http://www.ostrecovery.ostpst.org