MPUI player refuses to play

MPUI player a standard player for media players is suddenly not playing. When a file is loaded , it usually starts another application mplayer.exe which it suddenly reports as not able to start , even though it is available in the same folder. The error message.. command line: "C:\Program Files (x86)\Mediacoder\MediaCoder -4399E\codecs\mplayer.exe" -nogui -noconsolecontrols -slave -identify...