Okay here's my last thought to turn it to default state.
control panel - programs and features - Turn Windows features on or off
Scroll to media features
Untick media player and okay through it.
Reboot, go back to the same place and tick the box again okay through it.
If that doesn't return it to default/initial settings, I don't know what will.
even that isn't actually removing it, it's kind of disabling it and restarting it.