To do this, start by typing Windows Media Player in the Start search and click on the Windows Media Player link
Changes need to be made in the Library view, so if your player is in the Now Playing mode, you can switch to the Library by clicking the Switch to Library button in the upper right corner of the player window.
You can also access the Library by first hitting the Alt key. This will bring up a menu, from which you wll want to choose View>Library.
In the Library window, click the Organize button and select Manage libraries>Music.
When you see the folder list, click on any folder you want to remove. Click the Remove button and then click OK.
Another way to prevent unwanted additions to your Player, is to choose which media files are automatically included in the Library. This is done by turning off features in the Options dialog box.
Again, click on the Organize button. This time, select Options. This will bring up the Options dialog box.
If you want to prevent media files from being automatically added when they’re played, under the Player tab, uncheck the box beside Add local media files to library when played.
If you want to prevent remote media files from being automatically added, uncheck the box beside Add remote media files to library when played.