| mch | Machinery HDR Effects Settings |
| mcr | DataCAD Keyboard Macro |
| mcs | ModelCHECK Start Config |
| mdpf | Mac OS X Modem Preferences Data |
| mdrc | MADRIX DMX Remote Configuration |
| mgk | GraphicsMagick Configuration |
| mgk | ImageMagick Configuration |
| mhc | MPLAB Harmony Configuration File |
| milk | WinAmp MilkDrop Plugin Preset |
| mix | Daqarta Mixer Settings |
| mkp | Cinestar Remote Control Configuration |
| mkt | Microsoft Visual FoxPro Configuration |
| mm4 | Mortgage Minder 4.0 Mortgage Configuration |
| mmdc | MediaMonkey Device Profile |
| mmg | Mkvmerge GUI Preferences |
| mmpf | CodeWarrior Preferences Data |
| mmrc | MADRIX 2 MIDI Remote Configuration Data |
| mmrx | MADRIX 3 MIDI Remote Configuration Data |
| mobileconfig | Apple Mobile Configuration |
| moog | Moog Configuration |
| mpdconf | Music Player Daemon Configuration |
| mps | Casio WK-3000 Music Presets |
| msz | MADRIX 3 Compressed Setup |
| mtxcfg | MKVToolNix GUI Settings |
| mxu | MultiExchange Unit Configuration File |
| my | Yudit Settings |
| nacl | NameCleaner Internal Data |
| nam | Novell Netware Namespace Data |
| nanorc | GNU Nano Configuration |
| napr | NameCleaner Preferences Data |
| napt | Navicat Premium Data Transfer Profile |
| nca | Nikon Capture Color Adjustment |
| ncm | Nokia Configuration Message |
| ndc | IBM Personal Communications Connection Configuration |
| nkp | Native Instruments Kontakt Presets |