What is an NSF file? A file with .nsf (Notes Storage Facility) extension is a database file format used by the IBM Notes software, which was previously known as Lotus Notes. It defines the schema to store different kind of objects such like emails, appointments, documents, forms and views. All this information is contained in a single NSF file for business collaboration similar to a PST/OST file. Some of the applications that can open NSF files include IBM Lotus Notes and IBM Domino.
