It wouldn't surprise me at all if Outlook doesn't know how to read/import a standard mbox file, but I'm sure you could use Thunderbird or something as an intermediate 'converter'. By that I mean that you could import into Thunderbird then export from there to something that Outlook could work with.
It wouldn't surprise me at all if Outlook doesn't know how to read/import a standard mbox file, but I'm sure you could use Thunderbird or something as an intermediate 'converter'. By that I mean that you could import into Thunderbird then export from there to something that Outlook <em>could</em> work with.