Use the OST to PST Converter tool, which can easily convert single as well as multiple emails from OST files to PST format at a one time. It is the right way to split large size of Outlook OST file in small parts. The OST to PST Conversion utility also export OST file to PST file format. The OST viewer tool supports all versions of MS Outlook and windows OS. You can try free demo versions of the OST to PST software which converter a few emails from Outlook OST to PST,, office 365 account Live Exchange server, Gmail, OLM, NSF, EMLX, vCal, vCard, EML, MSG, HTML, Zimbra, PDF, MBOX, and etc. You give accurate results after using the software. You can operate the tool without any technical knowledge.
How to Convert OST to PST