Download the eSoftTools OST to PST converter program if, as I hope, you want to open OST files without an Exchange server. These programs make it simple to convert OST to MBOX file and also Gmail, Office 365, vCard, EMLX, and HTML. After conversion, opening an OST file in Outlook is simple. This tool has many other features, like email filtering, recovery advice, split PST file, OST to PST converter, naming conversion, save location, and more. It is completely virus-free software. 

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