MailsDaddy OST to PST converter is the reliable tool which used and recommended by industry experts. It converts bulk OST files to PST without altering the folder structure and maintain its data integrity. Exports OST files in multiple format such as Office 365, EML, MSG, HTML, RTF, and many more. Also has filter option that helps user in sorting the emails, attachments using read/unread status, subject, from, etc.