The simplest way which is recommended by most of the users to convert NSF file to PST file is by using a tool like eSoftTools NSF to PST Converter tool. It identified the .nsf file on its own and then exports information into 9 different file formats. This includes EML, EMLX, HTML, MSG, vCard, PST, vCard, etc. The hierarchy remains as the original after conversion and this tool works fine with corrupted NSF file. Each component of the software can be restored without any alteration which may include emails, contacts, notes, calendar, etc. A free demo version is also offered to each user with support to all editions of Lotus Notes and Outlook.
Explore more: http://www.nsftopstconverter.esofttools.com/