If you still searching for the best solution to export offline OST into Office 365, try MailsDaddy OST to Office 365 Migration Tool. This professional software easily import OST files into Office 365 without any changes in the folder structure and text formatting. The tool migrates all emails, calendars, journals, tasks, etc, and provides error-free results. Before migration, the software shows the preview of all OST file databases in the preview section. Here users can easily migrate multiple OST files into one or more Office 365 accounts at a time.

Using this solution users can perfectly upload OST files into Office 365 Primary and In-Place Archive Mailbox. This application smoothly works in all Windows versions. Its free demo version helps you to transfer the first 20 email items from each folder without facing any kind of problem.

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