But no matter how good your antivirus program is, if you open a suspect email, you make yourself vulnerable to Trojan horses that steal email and bank-access information.

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"Although the conditions to be checked may change over time, current experience suggests that such health checks should ensure that software patches are applied, a firewall is installed and configured correctly, an antivirus program with current signatures is running, and the machine is not currently infected with known malware, " he wrote in the accompanying paper.

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Many feel that patching tools, a regular and fully automated backup program, and a strong recovery toolset are more effective in dealing with the risk than antivirus software.

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