Good tool of KDETools Outlook OST to PST Converter software. This is a powerful tool to transfer OST files with all internal elements task, Reminders, Contacts, calendars, alarms, trashed folders, and user-defined folders, etc. with the help of Outlook OST to PST Converter software to converts OST file into PST and other file formats such as PST Outlook , office 365 account, vCard, vCal, Gmail, live Exchange sever, zimbra, MBOX, EML, EMLX, NSF, HTML, PDF, OLM, and etc.