To restore ost file in pst file by using outlook ost conversion tool which is the able for recovery outlook ost file. The free ost to pst converter open source tool to fix outlook ost file and also export OST to PST, Office 365 account, pst file, EML, EMLX, MSG, HTML, MHTML, MBOX, VCF, CSV, ICS, Live, Exchange Server, Zimbra, Gmail, Yahoo, and etc.