The best-rated third-party solution to convert MBOX to NSF file is the eSoftTools MBOX to Outlook Converter. MBOX conversion does not necessitate the usage of the Outlook application. File formats that can be converted include HTML, CSV, EML, MSG, Office 365, PST Outlook, and vCard. This utility can convert and divide any size MBOX file into smaller multiple PST files. Because of its broad feature set, this utility can convert and divide any size MBOX file into smaller numerous PST files.