When dealing with large or orphaned OST files, choose a converter that supports mailbox scanning, preview, selective export, and batch processing. MailsDaddy OST to PST Converter is worth considering because it supports orphaned, inaccessible, encrypted, and corrupted OST files. It allows users to export emails, attachments, contacts, calendars, and other mailbox items into PST format while helping maintain the original folder hierarchy. Additional features include date filters, advanced search, and options to split large resulting PST files. The tool also supports exporting data to EML, MSG, MBOX, HTML, and PDF formats. Before converting important mailbox data, preview the contents and keep a backup of the original OST file.