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With up to 55,000 new pieces of malware released per day and the Zeus Trojan horse infecting millions of PCs, the Internet may seem like a scary place. The best way to fully protect yourself from these and other advanced cybercrimes: ensure your anti-virus software is updated daily, an Internet security expert told FoxNews.com.

Dave Marcus, director of security research and communications at McAfee Labs, said daily updates coupled with slight behavioral modifications is the best two-pronged approach to avoid attracting Internet viruses like the Zeus Trojan, which he characterized as "professional grade" malware.

"As you and I are having this conversation, malware is being pushed out," Marcus told FoxNews.com on Thursday. "If device x has value, it's ultimately going to be a target. That's for sure. It's a cybercrime-driven landscape today," he said.

Aside from the latest anti-virus protection, Marcus suggested that users be wary of every e-mail they receive. Depending on the time of year, Marcus said up to 92 percent of all e-mail traffic is spam.

"Looking at your in box with suspicion is a good behavioral change," he said. "If it's not asked for, you've got to treat it as suspicious at the least, or possibly malicious."

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Marcus also recommended that computer users change their passwords as frequently as every 60 days, and that they ensure that firewall software is part of their everyday anti-virus package.

"I am not intimidated to do online banking because I take precautions and I also modify my behavior as necessary," Marcus said. "As long as you understand the threat and risk, you should be OK."

Marcus also warned that the latest Zeus variants are capable of bypassing SMS text message authentication used by some European banks, much in the same way a hacker would use a phony e-mail to access a user's machine.

"The user is being sent a text message with a link," he said. "That's a common technique." And as is the case with e-mail, Marcus said to treat every text message with caution.

In fact, Marcus said, hackers have become so advanced that viruses such as the Zeus Trojan are developed in the same way a regular firm would produce software.

"The fact is that they distribute it, maintain it and support it," Marcus said. "It's developed and maintained like a product. They have forums and bulletin boards; I wouldn't be surprised if they had an 800 number. That's both an impressive and scary thing."

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