When file sharing software is installed on your computer, you risk breaking the law, but there are other things to worry about as well:
By default, many file sharing applications have settings enabled that automatically share the contents of at least the "Downloads" folder of your hard drive. So if you have a filesharing application, you may enable other people to download copyrighted material, which is illegal even if you obtained the music legally.
File sharing software often comes packaged with ad- and spyware, so your computer is also likely to be sharing information about you, as well as running much slower than it should.
Many shared files now contain viruses and other malicious software, so by downloading files you risk the health of your computer.
For all these reasons, Simmons urges you to remove file sharing software from your computer. Even if you don't think that you have any such software, you should open the Control Panel on your computer, double-click on Add/Remove Programs, check to see if you have any file sharing programs. If you find one, you can click “remove” if you wish to uninstall it.