Home : File Types : MUI File (2 File Associations)

.MUI File Extension

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File Type 1Myriad Instrument File

DeveloperMyriad Software
4.0 (52 Votes) Thanks for voting!
Rare Uncommon Average Common Very Common
CategoryAudio Files


File format categories include Binary, Text, XML, and Zip. The format of this file type has not been determined.


Instrument file used by Myriad musical notation software products such as Harmony Assistant; stores instrument sounds and can be for piano, strings, woodwinds, brass, or a variety of other instruments; used for generating realistic sounds.

Program(s) that open .MUI files
Microsoft Windows LogoWindows
Myriad Harmony Assistant
Mac OS X LogoMac
Myriad Harmony Assistant
Linux LogoLinux
Myriad Harmony Assistant
Updated 4/11/2012

File Type 2Multilingual User Interface File

3.9 (164 Votes) Thanks for voting!
Rare Uncommon Average Common Very Common
CategorySystem Files


This file is saved in a binary format, which requires a specific program to read its contents.


Resource file used by the Multilingual User Interface component of Windows 2000 and later; contains resources that allow the Windows interface to be changed to different languages.

More Information

Many MUI files can be found within the Windows %SystemRoot%\ directory (e.g., %SystemRoot%\en-US\ in Windows 7). They may also be located within specific program installations, such as Windows Journal, Windows Defender, Windows Mail, and other Microsoft Windows programs, including Notepad (notepad.exe.mui).

Additional language packs can be installed in Windows 7 by selecting Control Panel → Clock, Language, and Region → Change display language → Keyboards and Languages and clicking the Install/uninstall languages... button.

Program(s) that open .MUI files
Updated 7/1/2010