I want to tell you the best way by which you can extract emails from MBOX files. So you use the most recommended software that is easy to use: SysInspire MBOX to PST Converter tool. This is the perfect solution to your MBOX file problem because it can convert different emails to client media like PST, VCF, EML, EMLX, HTML, Office 365, Yahoo Mail and many more. This software cannot damage any element present in the MBOX file like contact calendar, background and font style etc. you can open this software in any window of the PC and also it can support all editions of MS Outlook 2019, 2016, 2013, 2010, 2007, 2003. 

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