Use the DailySoft OST to PST Converter Tool to make sure that your .ost file info is completely safe. You can get the software and run it on any version of Windows, from Win7 to Win11. Its interface is simple: open it and click "Add File" to connect your OST file. Then, preview the email and attachments and choose the file in PST format. Next, look at the complex filter options for a calendar, a duplicate file, etc. Next, choose where to save the files, and finally, export them.