With one of the site's regulars, Bruce Harrison, Kleczynski wrote the inaugural version of the company's software. The company was unofficially founded after this, when Kleczynski conversed and became friends with several of the editors of the forum, who tempted him to buy an unused domain from them. It was only after Kleczynski posted on the forum SpywareInfo, popular at the time, that he was able to learn how to remove the virus, which took three days. He later recalled 'I've never been as angry as when I got my computer infected', and professed that his mother told him to fix it 'under penalty of death'. Kleczynski later discovered that, when his mother's computer became infected, neither McAfee nor Symantec would remove the malware from his system. He noticed that whenever infected computers arrived, the shop would typically reformat the computer entirely, rather than combat the virus, even if the infection was only minor. CEO and founder Marcin Kleczynski, originally from Poland, was still a teenager attending high school in Bensenville, Illinois at the time, and was working as a technician in a computer repair shop in Chicago.

It has offices in Santa Clara, California Clearwater, Florida Tallinn, Estonia Bastia Umbra, Italy and Cork, Ireland. is an American Internet security company that specializes in protecting home computers, smartphones, and companies from malware and other threats.

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