Everything often faild to run a file and send it to Windows Media Player (default player)
A while after pressing Enter on an audio/video file, I'm getting this:
Running from within Explorer works.
(Seem to recall, something, from days of old, where Windows would "hold open" certain media files, forgot why ? maybe to scan for tags or some such, & if it hit a file that was "awkward", there could be a delay...?)