Despite repeated warnings from CIOs, security administrators, and others in management, workers continue to open E-mail attachments from unknown senders and visit Web sites infected with spyware and other types of malicious software. It's clear that if users have access, they will click. And that opens the door for dangerous threats to find their way into business systems and networks.

GreenBorder Inc. this week rolled out security software for PCs, to go along with its server software, that is designed to prevent viruses, Trojan horses, spyware, and other malicious software from penetrating computers systems and networks. IT mangers create a list of trusted software in the vendor's Intelligent Security Application Barrier application that keeps security threats from affecting a user's PC operating system, files, and connections. The product lets security administrators use virtualization to create a shadow network for any untrusted traffic attempting to enter a business' IT infrastructure. Only trusted data moves on to the real network. As sources of information and specific kinds of traffic earn a company's trust, they can be added to the trusted list and gain access the real network.

GreenBorder's software works directly with Microsoft Internet Explorer and Outlook to monitor and manage traffic coming in via E-mail and Web sites. The software will be available directly or through resellers; the Professional Edition is priced at $60 per Explorer seat, $25 per Outlook seat, and $4,995 per Windows server. The vendor will also offer a free version for home users over the Web.

The GreenBorder software is notable because it can work with a wide range of networking products and standards and monitor a variety of network traffic, says Peter Lindstrom, an analyst at IT security research firm Spire Security. He says the approach of setting up a duplicate network and operating environment for untrusted traffic, while allowing trusted traffic to make its way to the real network, is unusual and appears to be effective. Says Lindstrom: "The untrusted information is reduced to shadow boxing, and nothing happens."