You can manually convert OST to PST only when you are using Outlook with the original Exchange account but If you want to convert original exchange profile then you should use any third party software. I personally recommend you this professional and brilliant OST to PST conversion software. With this tool you can easily removes Synchronizing error, File size error, Virus attacks and Trojan errors and repair damaged and corrupted OST File and convert OST File data into several kinds of formats such as- PST, EML, MSG, HTML, EMLX, MBOX and vCard format along with emails, contacts, calendars, task, notes, inbox items, outbox items and appointments.

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