Importing an offline OST file into Office 365 can help users access mailbox data after an Exchange account becomes unavailable or when migrating to Microsoft 365. Since OST files are linked to specific Outlook profiles, directly importing them into Office 365 is not supported. A professional OST to Office 365 migration tool can extract emails, contacts, calendars, tasks, and other mailbox items from an offline OST file and transfer them directly to an Office 365 account. These tools can also handle orphaned or inaccessible OST files and preserve folder structure during migration. The process provides a convenient way to move offline Outlook data to Office 365 without manually recreating mailbox content. https://medium.com/@avasmith16420/import-offline-ost-to-office-365-753fe6dc3df2

Extracting emails from an MBOX file is simple with a reliable MBOX Email Extractor tool. It scans the MBOX mailbox, previews all email folders, and lets you extract emails while preserving the original formatting, attachments, metadata, and folder hierarchy. The software supports MBOX files created by Thunderbird, Apple Mail, Eudora, and other email clients. With advanced filtering options, users can extract specific emails by date, sender, or subject, making email backup, migration, eDiscovery, and data recovery fast, accurate, and secure. https://zamstudios.com/blogs/how-to-extract-emails-from-mbox-file/