The fear of phishing scams and online fraud is undermining people's trust in the Internet and it's taking a big bite out of e-commerce.

Insight Express recently conducted a survey for Symantec Corp., an information security company based in Cupertino, Calif. The survey shows that 43.5 percent of all respondents receive unsolicited emails requesting personal information several times a day. And 44.2 percent say they think they have visited a fraudulent Web site, but they're not sure.

And because of these high percentages, Bill Rosenkrantz, group product manager for Symantec, says 74.3 percent of respondents only buy products through secure sites. But a full 45 percent don't provide confidential data over the Internet at all. That means 45 percent don't shop online because that would require them to give out their credit card numbers, along with other personal information.

And that means Amazon.com isn't selling books to that 45 percent. They're not battling it out in eBay auctions, and they're not ordering hiking boots from L.L. Bean's Web site.

''When almost half the population says they're not going to provide information over the Internet, it says to me that consumers are not embracing the Internet and have a lack of trust of online transactions,'' says Rosenkrantz. ''It is definitely undermining people's trust. It's impact on e-commerce is harder to gauge but if it hasn't already, it has the potential to stall growth.''

Phishing scams, which are dramatically increasing in frequency, are the latest type of online fraud. Scammers send out spam, pretending to be legitimate businesses or financial institutions. Using social engineering tactics, they try to convince the user that there is a problem with their online account or that some information has been lost. They then entreat the user to click on a link which takes them to a Web site that is set up to look like the legitimate Web site, but is only mockup for the scammer. Once the user puts in his credit card number, or password or bank account information, the scammer can rob him blind.

While phishing scams are only one form of online fraud, Rosenkrantz said they focused their survey on it because it has received so much attention lately.

''We needed to know to what extent do phishing attacks impact people's overall trust of the Internet,'' he explains.

Rosenkrantz also says the survey shows that 93.9 percent are somewhat or very concerned about phishing attacks. It also shows that 31.5 percent don't use the Internet for online banking.

And while the majority of respondents say they haven't been the victim of online fraud or identity theft, 86 percent of those who have not been victims have changed the way they use the Internet.

Rosenkrantz says businesses are suffering financially because of the fear and mistrust out there.

''Business people are saying they can't communicate with their consumers because the customers can't distinguish between legitimate emails and phishing scams.''