SpyBot Search & Destroy is the best spyware-remover available, and it's free. I recommend also using Ad-Aware, as both SpyBot and Ad-Aware can find and remove things the other can't. I still recommend using the firewall and DNSKong to prevent future infections. SpyBot has a built-in update feature which is safe to use and you should check for updates from time to time. Due to overwhelming popularity, there is a second, "mirror" site set up here. This is a must-have.
Lavasoft's Ad-Aware is another good, free spyware-removal tool. This is also a must-have. Like everything else recommended here, it's free.
Merijn Bellekom's CWShredder is currently the only software in existence that can eradicate all known variants of the ultra-nasty CWShredder series of trojans. Like just about everything else here, it's free.
Javacool's Spywareblaster is also a good anti-spyware tool. Javacool makes a lot of neat anti-spyware and anti-tracking tools. like ID Blaster, FileChecker and other nifty tools.
As you can see, these three programs are key to preventing the most common privacy and security violation in existence: spyware. All three are free, but I recommend sending donations to the authors. They really work hard, and believe me, they have prevented millions of people a lot of grief. Maybe more.McAfee's is a good product and, like Norton's, buying it will entitle you to a 1-year subscription to updates. Also, it may come bundled with a firewall and other stuff. The firewall is awful (almost as bad as Norton's firewall), but the other stuff is okay. It's usually around the same price.
F-Prot is a decent anti-virus program that, depending on the version, can be free or paid. The free version is a DOS version and I don't think it is very good at removing viruses. If you're very computer-savvy that probably won't be a problem as long as you know it's there. I have no personal experience with the paid versions but they are reportedly pretty good. I think they give you a 1-year subscription also.
Kaspersky's is a top-rated one that I have experience with. I believe you can try it for 30 days before buying it and you get a year's subscriptions to updates.
AVG by Grisoft is free for personal use. I would only rate it as so-so but since some people aren't willing to buy software I included it here. It's better to have something than nothing.
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