How to convert OST Outlook folder to Office 365? To convert OST Outlook folder to Office 365, download and use the advanced OST Converter tool as software helps you to convert OST Outlook folder to Office 365 in simple and easy steps. All through the OST Outlook folder to Office 365 conversion process software includes total OST files meta data, email attachments, embedded images, signatures, etc into Office 365 location in secure manner. Free to try OST Converter mode is available, download the free OST Converter tool now to test its working ability.