No surprises here that the majority of computer users are clueless about the increasing threat of spyware. McAfee has revealed that 97 per cent of users have no idea how to spot spyware, and don't know what to do about it.

Its SiteAdvisor branch gave users a test to see if they could identify the clues that indicated that something was spy or adware.

Only three per cent of the 14,000 who took the test got perfect scores.

McAfee believes that the responses of the 14,000 who took the test indicate that over half may be seriously infected, with even those who seemed to know what they were doing have a good chance of visiting a dangerous site.