Are you still searching for a safe and dependable technique to convert OST to PST? I advise using the well-known and effective option for conversion. You can save OST mailbox contents to PST, EML, EMLX, MSG, MBOX, vCard, HTML, NSF, OFFICE 365, and other file formats using the eSoftTools OST to PST Converter. There is also a free trial version available to test the utility's performance, which allows you to export 25 emails per folder at no charge.
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Convert OST to PST Manually
Open Outlook and go to the File menu.
Select the Import/Export option.
Choose Export to a file.
Select Outlook Data File (.pst)
Choose whether to export a specific folder or the whole account.
Check the Include subfolders box.
Next, select a destination for the Export, and then click Finish
Regards,
Willjoe