MS Outlook users- You can try Outlook ost to pst converter software. It is the best solution to convert ost to pst Outlook manually.  The ost file converter freeware tool completely works to conversion files from damaged ost to new pst file after fixing outlook ost file. This OST converter software has Batch option that is the simple selects file/folder for converting ost file to pst file. 

1- Transfer ost to pst file, Office 365 account, pst file, EML, EMLX, MSG, HTML, MHTML, MBOX, VCF, CSV, ICS, Live, Exchange Server, Zimbra, Gmail, Yahoo, and etc.  

2- Split large PST file in small parts.

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