S3 - Major
Whenever I open or try to open musescore it just doesn't. No "Musescore crashed" popup, it just refuses to open. I checked task manager, I set it to open as administrator, I tried everything I could think of. I'm on Windows 10 if that helps.
There may be another instance of MuseScore already running. Look in the Windows task manager and if you see one, terminate it.