You can use FixVare OST to EML Converter, a complete and secure utility that supports all OST types of files, including corrupted and orphan OST files, to convert OST to EML file format without any data loss. It maintains the folder hierarchy, properties of email, attachments and metadata in the whole process. This method guarantees zero data loss, fast outcomes, full accuracy and is best suited for users who want to safely access and migrate Outlook emails to a client like Thunderbird, Windows Live Mail or Apple Mail.