| mgn2 | Bloody Mouse Macro Data |
| mgo | MacGourmet Recipe |
| mgrp | NI Maschine Group File |
| mgrs | Military Grid Reference System Data |
| mgspot | MacGourmet Spotlight MetaData |
| mgtheme | MacGourmet Theme |
| mgw | Microgateway Policy Implementation Data |
| mgz | Compressed MGH MRI Data |
| mhd | ITK MetaImage Header |
| mhe | Hackshield Heuristic Engine File |
| mhg | MHEG-5 Multimedia Data |
| mhl | Media Hash List |
| mhm | Microsoft Mouse and Keyboard Center Macro |
| mhp | Maths Helper Plus Data |
| mhr | OpenAL Soft HRTF Data |
| mhs | Xilinx Microprocessor Hardware Specification |
| mhtmlenx | Egis Encrypted MHTML Data |
| mi2 | AutoDesk Softimage Data |
| miaf | InstallAware Setup Dialog Rules |
| mib | SNMP MIB File |
| mibs | PLINK Identity-by-state Matrix Data |
| midata | Mine-imator Data |
| mif | Xilinx CORE Generator Memory Initialization File |
| mif | Elmer Mesh Generator Input File |
| mif | mAirList Inline File |
| miframes | Mine-imator Keyframes Data |
| migrated | Microsoft Windows Migrated Data |
| migtable | Microsoft Windows Migration Table Data |
| mihb | eXtendable Wad Editor MIHB Data |
| miigx | SaveGame Manager GX Mii Data |
