The safest and easiest way to convert OST to PST Outlook with the support of third party tool, then I suggest you to attempt this eSoftTools OST to PST Recovery software without any doubt. This multi functional tool is able to export any size of Offline OST file into PST, EML, MBOX, CSV, vCard, MSG, HTML, cloud 365 and keeps the structure original. It is capable to run on dissimilar Microsoft Outlooks such as 2016, 2013, 2010, 2007, 2003, 2000, 5.5 and 5.0. The tool is designed to run smoothly on all Windows platforms: including 2016, 2013, 2010, 2007, 2003, 2002, 2000, 98 and 97.
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