Kazaa is a horrible program. On their website, before clicking the link to download this piece of shit, I read this: "No adware or spyware!" Well, after installing it there were shortcuts about casino gambling and mortgages on my desktop, as well as 6 other hidden programs in my file structure, including one that uses your pc as a component in a network for some company that does god knows what. All this stuff was on my pc right after the install- I didn't even use the program!!!!
Kazaa is in legal battles, and to financially support these has resorted to flooding your pc with ads and all sorts of junk. Here's something to ponder: Kazaa claims not to install spyware on your system, but the ads and programs that flood your pc are based on your browsing habits. If you browse cars, you'll get car ads. If you browse the net for movies, you'll get movie ads. Kazaa doesn't magically know your browsing habits- there is a program hidden in the file structure that spies on you while you are online..... If this isn't "spyware" then what the hell is their definition? They can add false advertising to their list of lawsuits.
It took me 2 hours to get rid of this crap completely. Whatever you do, do not use Kazaa. Just stay far, far away. It doesn't matter what kind of antivirus or firewall you have, trust me. If you can use Kazaa, then it is unblocked and unaffected by your firewall, and will pretty much do as it pleases. Kazaa is a joke of a program, and I will throw a party when it dies in the courts.
If you want a great file sharing program that is much faster and safer than Kazaa, get Limewire; I've NEVER had a single problem with it. There are no ads and no spyware. It just works, and does all that Kazaa claims, minus the lies and mountains of bullshit.
Kazaa sucks sweaty, hairy balls