MMDiag.exe refers to an executable file associated with Musicmatch, a very popular media-playing software in the past. Through Musicmatch, users can play their favorite audio files that are stored in the computer and mix them up with songs that are stored in compact disks.  In order for the Musicmatch software to run properly, it needs to activate several files including MMDiag.exe.  In terms of location, mmdiag.exe is typically stored under its own program or parent folder.  Under the windows operating system or environment, Musicmatch will be created with its own folder under the Program Files folder.  Files associated with the Musicmatch software including mmdiag.exe may be located in its own folder.

Musicmatch was the original name of the company and the released audio player or software.  Later on, the media player was renamed to Musicmatch Jukebox along with some updates to its features and capabilities.  Other related prod

ucts were also released by the same company including Musicmatch Radio and Musicmatch On Demand among others.  By 2004, the company was bought by Yahoo! Inc. which led to the rebranding of the audio and media player as the “Yahoo! Music Jukebox”.  In September of 2008, Musicmatch under Yahoo Inc. eventually ceased to operate.

People with older computers may still encounter errors that point to the mmdiag.exe file.  This simply means that the computer involved was previously installed with the Musicmatch media playing software. For users that do not use Musicmatch anymore, errors that relate to the mmdiag.exe file may be a red flag for virus infection or malware.  If the Musicmatch program is not needed, users may opt to have this uninstalled to take care of errors relating to the mmdiag.exe file.  Otherwise, if there are concerns with the mmdiag.exe file that may be suspected of being an infected file, deleting the file or the whole program associated with it may be a good option to take.