Not sharing your files isn't going to stop you from getting a virus...if you download infected files & don't scan before opening them, that's when you'll get a virus. And if you're unknowingly sharing infected files, the people downloading from you may end up infected as well.

What you have to do is make sure that you're using a good antivirus (AV) program. keep it updated & scan every file that you download, before you open it. Watch file sizes in your search results & avoid files smaller than about 2000 KB. Also watch file extensions & make sure you don't download anything that's marked mp3.exe, or any music which shows a program icon instead of a music icon.
WARNING: Viruses on network you should be aware of!

The Bill clinton spam's been around for a while & most of the time it's just annoying...I guess some of those files are more than just spam.
the pres(Clinton spam file)
That Irritating Bill Clinton Cel Phone Ad

If files that used to be ok have suddenly started with that spam message, sounds like you've picked up some malware. Update your AV & scan your computer. If you don't have an AV program, here are some good free ones.
avast!
AVG free
Avira Antivir

And it's worth your while to scan for spy/adware too. These programs are all free.
Spybot S & D (free)
AVG Antispyware (formerly Ewido)
Ad-Aware SE Personal (free)

You absolutely cannot get rid of a virus by uninstalling/reinstalling LW!! If you're still having problems, try one of these sites for more specialised help.
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