I had to convert some old Outlook PST files to MBOX so I could open them in Thunderbird. I looked around for the perfect tool and chose Mailvita PST to MBOX Converter. I'm glad I did. The interface was easy to use and clean. I didn't have to sort through any complicated options. I just added my PST files, looked at the emails, and picked the ones I wanted to change. The software operated flawlessly, and the final MBOX files displayed a smooth organization with no missing items. I wasn't sure about a setting at one time, so I called their support personnel. They got back to me right away and helped me through it without any trouble. This tool helped me save a lot of time and stress in general. I would certainly suggest trying the tool if you are switching email clients or just need to back up your Outlook emails. It just works.
mailvita-pst-to-mbox-converter-for-mac