| las | Light-O-Rama Animation Sequence |
| launch | Zend Studio Debugger Configuration Data |
| lcc | Light-O-Rama Channel Configuration |
| lcc | Capture One Lens Cast Correction |
| lct | Oracle Generic Loader Control File |
| ldr | WindLDR Ladder Diagram |
| ldt | Belkin Loadout Manager Data |
| lfo | Alchemy Low Frequency Oscillator Presets |
| lily | PCSX2 LilyPad Configuration |
| lir | ADI Ocelot Configuration |
| list | APT Package Resource List |
| lks | WinAMP Links |
| lnst | Adobe InDesign Line Presets |
| lr | Chaos Desktop Layer Settings |
| lrsmcol | Adobe Photoshop Lightroom Smart Collection Settings |
| lsv | Light-O-Rama Preferences |
| lvlps | LabVIEW Local Project Settings |
| lvt | Land Surface Verification Toolkit Configuration |
| lxc | Linux Containers Configuration |
| lxcp | LCARS x32 Color Profile |
| m2m | TiMidity++ M2M Settings |
| m4l | Sage MAS 90 Panel Settings |
| mal | MadAppLauncher Configuration |
| mbc | ModBus Configuration File |
| mblook | Magic Bullet Looks Presets Data |
| mbxcfg | Molebox Configuration Data |
| mca | Massive Midi Setup |
| mce | Sixense MotionCreator Game Profile |
| mch | Machinery HDR Effects Settings |
| mcr | DataCAD Keyboard Macro |
| mcs | ModelCHECK Start Config |
| mdrc | MADRIX DMX Remote Configuration |
| mgk | GraphicsMagick Configuration |
| mgk | ImageMagick Configuration |
| mhc | MPLAB Harmony Configuration File |