SpyBot Search & Destroy Portable is a free internet security program specializing in removing malware, spyware, and adware.
They now have Spybot +AV, an advanced all-in-one internet security suite that includes many additional features such as antivirus protection and many other useful tools such as Live Protection, Regalyzer, Filealyzer, File Shredder, iPhone Scanner, and more. You can read more about that by following the Author's Link above.
The latest definition updates can be found here.
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