John McAfee fundamentally changed the way we target computer viruses

John McAfee may be best known for his erratic and eccentric personality, but his contributions to cybersecurity can’t be overlooked. McAfee, who died by suicide in a Spanish prison on Wednesday ahead of a planned extradition to the U.S. to face tax evasion charges, founded the eponymous software company that millions worldwide rely on to keep their computers safe.

The British-born McAfee, 75, worked in numerous jobs in the technology industry including a stint at NASA before founding McAfee Associates in 1987 after the first known computer viruses began to appear.

“From a security standpoint, he wrote, really, the first antivirus software that scans for many viruses at once,” explained NYU Tandon School of Engineering professor Justin Cappos.

Prior to McAfee’s software, viruses were found and captured on computers one at a time. A person would have to install a program to take care of virus “A” and a program to take care of virus “B,” and so on. McAfee’s innovation allowed users to scan and capture viruses en masse.

McAfee had the benefit of first mover advantage, beating eventual rivals like Norton to market, and the then-burgeoning use of the internet among businesses and consumers. As viruses proliferated, McAfee became the go-to brand for antivirus solutions.

“At the time when it came out, certainly there was a window of time in the late ‘90s, or so, where it was actually important to have an antivirus [program] and Windows didn't come with one,” Cappos explained, referring to Microsoft’s now built-in Windows Defender antivirus program.

“The internet was just starting to happen, computers were just starting to be more connected together, viruses were starting to run rampant,” he added.

McAfee cut ties with the company in 1994 and sold the remainder of his shares for $100 million. The company, however, would continue to perform for years, as more consumers and businesses around the world connected to the web.

Intel purchased McAfee in 2010 for $7.68 billion. McAfee eventually moved to Belize in 2008 where he was embroiled in controversy. A facility he ran to produce herbal antibiotics was raided by authorities on suspicion of being a meth lab. He left the country in 2012 following the fatal shooting of his neighbor Gregory Faull. McAfee and Faull had an acrimonious relationship at the time, according to various media reports.

In 2013, Faull’s daughter filed a wrongful death suit against McAfee. She won the suit, and McAfee was eventually ordered to pay $25 million in damages.

The millionaire eventually settled in Tennessee where he lived with his wife and armed guards. He left the U.S. in 2019 to avoid trial for tax evasion in Tennessee and spent much of his time on a massive yacht with his wife, dogs, and the guards.

He was arrested in Barcelona in October, where he was awaiting extradition on the tax evasion charges. In March, federal prosecutors in the U.S. also indicted him in connection to a crypto currency fraud scheme.

McAfee was a frequent Twitter user, with 1.1 million followers, and regularly stated that he was wanted by the government for speaking out on taxes, and that the U.S. was trying to silence him.

“I am charged with tax fraud - which is lying on your tax return. But I have filed no returns for many years and have made no secret of it. If I have said nothing, how could I have lied?” McAfee tweeted in October.

McAfee, according to Reuters, still had a chance to appeal his extradition, but his lawyer said that his time in prison brought him to despair.

“He, I think, also, maybe saw shadows, where there weren't any and had sort of a reputation for that,” Cappos said.

Antivirus programs still maintain their popularity among consumers, and businesses seeking to protect themselves from the myriad forms of malware circulating on the internet. But with improved security capabilities from operating systems like Windows (MSFT), and Apple’s (AAPL) own iOS, antivirus programs have become less of a necessity for the everyday user, Cappos explained.

Instead, keeping your operating system and programs updated, and understanding basic cybersecurity hygiene, like deleting emails from unknown users, can help ensure users’ safety online.

That said, McAfee’s influence on the world of cybersecurity can’t be overstated.

Got a tip? Email Daniel Howley at dhowley@yahoofinance.com over via encrypted mail at danielphowley@protonmail.com, and follow him on Twitter at @DanielHowley.

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