If you want to open OST files in Outlook use the SysInspire OST to PST Recovery Emails software is a tool that can export many different five file formats OST to PST, HTML, EML, EMLX, MSG, Yahoo, Zimbra, Gmail, and Office 365. The OST user can convert OST to PST Free Outlook file without MS Outlook installed and also can use the split feature of this software to reduce the size of large PST files. Free DEMO versions are also provided to every user and export 25 emails or items from each mailbox item.
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