MBOX is one of the most popular file extensions. It opens with 16+ emails clients. An MBOX file stores multiple data including emails, notes, journals, contacts and messages. MBOX stores mailbox messages in their original internet message format. No change in the content structure and format is noticed. All email properties are stored safely including name, cc, bcc, to, from etc…
There are 4 variables of MBOX—mboxo, mboxrd, mboxcl2 and mboxcl. Eudora uses mboxo variation. Netscape and Thunderbird use an mboxrd format. MBOX file extension doesn't support Outlook for Windows. If you want to open an MBOX file to Outlook, conversion is must. Purchase the conversion license like MBOX to PST, MBOX to OST or MBOX to MSG to access MBOX data on Outlook for Windows.
Version 1.x of Apple Mail uses MBOX file format whereas the version 2.0 and its later versions use the EMLX format. Thunderbird of Windows, Mac and Linux support MBOX file format. The latest MS Outlook 2016 of Mac also supports MBOX. There are several other email clients that support MBOX like PocoMail, Entourage etc… Therefore, it is called as a versatile email program.
Choose MBOX as your file extension will not stop you to change your email client. You can switch from Thunderbird to Apple Mail easily and without paying anything. It means you don't need to get the conversion license. It sounds interesting for MBOX users.