As part of my transition to the Mac, I wanted to bring my email archives to OS X. I am currently using Apple Mail as my primary email program on OS X, but I also have Microsoft's Entourage available. I have about 5GB of old archived email that are store as a Outlook PST files. My first thought, of course, is that I could use Entourage to import my PST files, and then export them to a Mac Mail format. But alas, Microsoft's own Entourage program does not support Microsoft's own PST file format.
I turned to a little program called Outlook2Mac. It costs $10 but does a decent, albeit primitive, job of transcoding my PST into Apple Mail Mail Boxes. To my surprise, Outlook2Mac is a Windows program, I would have expected a Mac OS X program. The UI is very basic but does the job. Transcoding was fast, but it was often interrupted by a message box asking me if I wanted Outlook2Mac to fix the send date of certain message, or if I wanted Outlook2Mac to save a digitally signed message to an insecure file format. I wish they had a "Don't ask me again" option, as the message box popped up about 30 different times. Another limitation is that Outlook2Mac saves each email folder into a separate mbox file, instead of saving them all in a nested folder structure. As a result, my 3 archived PST email files have translated to 234 mbox files.
One hidden feature of Outlook2Mac is the ability to strip out all email attachments into a separate folder - this is great, I found long lost documents, and lots of photos that people have sent me over the years!
Thanks to Outlook2Mac I now have all my archived email available in a Mac friendly format. I hope that Spotlight can search the mbox files without me having to open them in Apple Mail. I don't think Apple Mail can support 234 Mail boxes :-)