| ngrr | Guitar Rig User Presets |
| ngs | NGSSniff Data |
| ngw | NGRAIN 3D Data |
| nhcode | Mastercam NetHASP Code |
| nhd | NetHelpDesk Page Data |
| nhm | Microsoft SMS NHM Data |
| nhx | New Hampshire eXtended Format Data |
| nick | Microsoft Outlook 2000 Auto Complete Nick List |
| nicrash | NI Traktor Crash Data |
| nid | Nikon Capture IPTC Data |
| nifcache | Gamebryo NIF Cache |
| nii | NIfTI-1 Data Format File |
| nil | Norton Icon Library File |
| nin | BLAST Nucleotide Database |
| niv | theWord New International Version Module |
| nix | IBM Rational XDE Node Instance File |
| njb | Nikon Photo Index |
| njf | Lotus Notes Job Data |
| nji | Nero BackItUp Job Information |
| njob | NDARC Job Data |
| njt | Nero BackItUp Job Template |
| nk2 | Microsoft Outlook 2002 Auto Complete Nick List |
| nka | NI Abbey Road Drummer Data |
| nkd | Nikon ViewNX Thumbnail Cache |
| nkg | Native Instruments Kontakt Groups |
| nkjv | theWord New King James Version Module |
| nksc | Nikon Capture NX-D Sidecar Data |
| nksf | Native Kontrol Standard Presets Library |
| nksn | Native Instruments Kontakt Settings |
| nkv | PLDA Shared Model |
| nl | AMPL NL Problem File |
| nlang3 | Ashampoo Internet Accelerator Localisation Data |
| nlb | Oracle Locale Builder Binary File |
| nlc | Nero Linux Compilation |
| nld | Norland Image Format File |
