1. Make sure that you have closed the Windows Media Player 11 window
2. Click on Start-->Run-->type in Services.msc and click on OK
3. Locate the "Windows Media Player Network Sharing" service
Note : The first thing you’ll need to do is go to Control Panel \ Administrative Tools \ Services for XP and look for the services that start with “Windows Media Player”. (Make sure Media Player is closed too)
4. Right click on it and click on Stop
5. Now click on Start-->Run-->type in %USERPROFILE%\Local Settings\Application Data\Microsoft\
6. Rename the folder "Media Player" to "Media Player.old" or something else that you wish.
7. Now open Services.msc from Start-->Run again and start the "Windows Media Player Network Sharing" service .
8. Open the Windows Media Player 11 and try to add music files to the Library.
