Opening an OST file directly in Outlook is not possible because Outlook only loads OST files linked to the same profile and Exchange account. If the profile is damaged, the system is changed, or the OST becomes orphaned, Outlook cannot open it. In such cases, the best solution is to convert the OST file into a usable PST format. eSoftTools OST to PST Converter Software allows users to easily open and access OST data by converting the entire mailboxincluding emails, attachments, contacts, calendars, notes, and tasksinto PST without losing data integrity. This tool works with corrupted, encrypted, or oversized OST files and preserves the original folder structure. After conversion, the PST file can be imported into any Outlook version with just a few clicks. The software also offers a preview feature to check mailbox items before exporting and supports multiple output formats, making it a dependable option for opening OST files in Outlook.