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If you require to transfer Outlook PST files to MBOX data format, for fast conversion and safe conversion, you can use the PST to MBOX Conversion Tool which is very simple to use or benefit from. No file size limitation to move PST files into MBOX file format. This tool comes with advanced and unique features for users to easily understand the working function of the application. I hope this tool helps you to convert data from Outlook PST to MBOX. Install the tool-free demo version of the application. Refer: https://www.sametools.com/convert/pst/