The GainTools NSF to PST Converter is a trusted application to utilize for NSF to Outlook PST conversion. It can migrate many NSF files into PST at a time and preserve all the email elements, including emails, attachments, Notes, calendars, etc. It can handle large NSF files efficiently. All Windows OS versions can be supported with this application. Having a simple and clear interface lets novice users operate the application without any effort.
Also read: https://www.gaintools.com/blog/switch-emails-contacts-calendars-attachments-lotus-notes-file-to-outlook-pst/
http://https//www.gaintools.com/blog/simple-ways-to-switch-nsf-to-ms-outlook-pst-file-format/