It's simple to convert OST file to a PST file with eSoftTools' OST to PST converter tool, which is so easy to use that no technical expertise is needed. It is not recommended to install MS Outlook to convert an OST file, and this software works with all versions of MS Outlook, including 2000, 2003, 2007, 2010, 2013, 2016, and 2019. eSoftTools, easily up to 25 emails can be converted into all formats.
Read More:- Convert OST to PST file
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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.