| 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 |
| nkfn | Kernel for NTFS Data Recovery Snapshot Data |
| 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 |
| nksr | NI REAKTOR Rack Data |
| nkt | nKPRO Telemetry Data |
| nkv | PLDA Shared Model |
| nl | AMPL NL Problem File |
| nl | newlook Screen Data |
| nl2 | eSignal Market Depth Data |
| nlang3 | Ashampoo Internet Accelerator Localisation Data |
| nlb | Oracle Locale Builder Binary File |
| nlc | Nero Linux Compilation |
| nld | Norland Image Format File |
| nlf | ClickTracks Normalized Log File |
| nlf | MicroSim PCBoard Netlist |
| nlg | Nestopia Language Data |
| nlk | Microsoft Outlook 2003 E-mail Cookies Data |
| nll | newlook Batch Script |
| nlo | Lotus Notes Linked Object |
| nlogo | NetLogo Model |
| nlogo3d | NetLogo 3D Model |
| nlp | NirLauncher Package |
| nlpe | Navicat for SQLite Exported Table |
| nlpev | Navicat for SQLite Export View Result Profile |
| nlpj | Navicat for SQLite Batch Job |
| nlpt | Navicat for SQLite Data Transfer Profile |