I’ve been trying to move some old Outlook for Mac email into another mail client, and I keep running into the OLM problem. Microsoft’s export process creates an OLM archive, but that doesn’t automatically make the data convenient to use in other email applications.

MBOX seems like a much more practical format when the destination is an application that supports it. I’ve seen people discussing OLM-to-MBOX conversions for Thunderbird and Apple Mail, and there are definitely situations where having the mailbox in a more portable format makes the migration easier.

I came across MacSonik OLM Converter while researching the options. The useful part is that it supports several output formats rather than locking you into PST. Depending on the destination, you can convert OLM to MBOX, EML, MSG, PDF, CSV, HTML and other formats.

I also like the idea of previewing and selectively processing the mailbox instead of converting everything without checking it first. For older archives, being able to work with emails, attachments, contacts, calendars, tasks and other mailbox data is important.

For anyone who has done this before, would you recommend converting the entire OLM to MBOX, or exporting only selected folders? I’m mainly trying to preserve the original email content and attachments while making the archive easier to access outside Outlook.