Hi Filbert,
Let's find out if there are other applications running at the background on the computer which are using Windows Media Player.
Refer to the links and follow the suggestions that are Marked as Answer:
You can also troubleshoot the issue by disabling the process that is using the media player:
- Press Ctrl+Shift+Esc, this will bring up the Task Manager, right click window media player in the Applications tab and select go to Process. This will bring you to the processes tab with the process highlighted for you. Right click that process and select End processtree. This will close Windows Media player.
- Open another music file by double clicking on it. Close Windows Media Player by clicking on the close button (X) for the player.
This will fix the issue.