If you want to convert your OST file to PST file, I highly recommend KDETools OST to PST Converter. The tool is the ultimate solution for converting your OST files into Outlook PST file. through this program, all MS Outlook users can easily convert your OST file into Outlook PST file included different file formats like- PST, Zimbra, Gmail, vCard, ICS, office MSG, EML, EMLX, MBOX, PDF, NSF, and etc.
More info- how to Convert ost to pst outlook
Do you want to convert OST files to PST format? If yes, then, you can try this CubexSoft OST to PST Converter software that helps you to convert multiple Outlook.ost files to PST in Outlook 2019, 2016, 2013, and etc. It converts all emails, contacts, calendars, tasks, notes, etc.
For More Info - https://www.cubexsoft.com/ost/pst.html