If you have several OST files and you want to open them within MS Outlook then OST to PST conversion is required. Once you save OST file into PST format; you can easily open it with any MS Outlook account.
OST to PST converter can easily export multiple OST files into PST format along with complete data like emails, contacts, calendars, tasks, notes etc. Software keeps the folder structure of OST file intact while saving them into PST format. It keeps the other properties and meta data of items intact.