I have an old Outlook OST file that contains a lot of important emails, and I need to access those emails in an email client that supports the MBOX format (like Thunderbird or Apple Mail). Unfortunately, Outlook does not provide any direct option to export OST files to MBOX. Can anyone please suggest an effective and reliable way to convert OST to the MBOX file format without data loss? I would prefer a solution that preserves email attachments, folder hierarchy, and metadata.