Some users have reported instances in which multiple context menu entries 

appeared for MediaMonkey 3.1. 

e.g. right-click on an MP3 file > Open With > MediaMonkey - Audio Library



Some users have found the following tool to be helpful for solving this:

http://defaultprogramseditor.com/



This can also be solved by manually editing the registry key for the associated file type.  

e.g. open the following in regedit:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.mp3\OpenWithList



Then delete all but the first MediaMonkey.exe key and any MediaMonkey (non-skinned).exe keys.

This needs to be done for all users/filetypes, so the best approach is to search the registry for

MediaMonkey.exe and delete redundant entries, pressing F3 to repeat until none found.