Tips for OST to PST conversion in Outlook. You can manualy convert data from OST file to PST with the help of Export/Import function in MS Outlook. After using this function you can easily export all OST mailbox data into new PST file format and if you unable to get complete data then you try for any 3rd party resource.
If you want more details about manual solution then read this blog post:- http://migrateemails.com/convert-ost-to-pst-format/