You can also go with Softaken OST to PST Converter. An advance way to converting unlimited OST files to PST at one time. It helps in converting OST mails, contacts, calendar and other folders to PST accurately. Preview pane is one of the best feature of the tool which allows you to view email files data before performing the final OST file conversion. You can go with free OST to PST Converter download edition which is available for free software evaluation and analysis. It enables to convert first 10 OST files to PST free of cost.