Tizen Developers

 Export mailbox as a PST file
Login to Outlook with the Exchange account that was used to create the OST files. And to export the OST mailboxes to PST, follow the simple procedure as given here:

Go to Files >Open & Export and click Import & Export.Import & Export
Select Export to a file; then click Next.Select Export to a file
Select the second option—Outlook Data File (.pst)—and click Next.Select PST file
Select the folder(s) which you want to export and click Next.Select the folder to export
Note: You have the option to include subfolders as well.

Browse the location where you want to save the new PST files and choose an option regarding the duplicate items.
Note: There is an optional choice to provide a password to the PST file, but you can easily move ahead without choosing it.

The safe and easiest solution to convert your Offline OST emails to PST is the OST to PST Converter Tool. With the help of this tool, you can easily transfer emails with attachments from OST files to PST. Additionally, when converting OST mailbox folders into a PST account, preserves the folder structure. It is effective at securely transferring both large and small email files. You can also move all of your files and information, including emails, directly to other email providers like MBOX or EML. It has sophisticated features, such as filters to locate certain email data and preview emails on any Windows version. Read more: https://www.osttopstapp.com/