Free Microsoft OST Converter Tool simply recovers the data from damaged Outlook OST files. Convert OST to PST and save all the data, such as exchange email messages, contacts, calendar items, tasks, notes and journals. Free Microsoft OST Converter Tool works fabulously on all the available versions of Windows operating system such Windows 2000, Windows XP, Windows Vista, Windows 98, Windows 7, Windows 8.1 and Windows 10.