Windows Vista has some way to go before Microsoft can consider it immune from online threats, according to security software manufacturer PC Tools. According to PC Tools, Vista is more susceptible to malware than even Windows 2000.

"Vista has been hailed by Microsoft as the most secure version of Windows to date. However, our research shows that it’s more susceptible to malware than the eight-year-old Windows 2000 operating system, and only 37 percent more secure than Windows XP," said Simon Clausen, chief executive officer at PC Tools.

PC Tools highlighted that as long as Vista has a small market share, targeted attacks will be less frequent. When market-share increases, however, there is a significant risk that the Windows Vista infection rate could rise.

"Since its launch, Microsoft has flagged the increased level of protection Vista provides as one of the key reasons why consumers should upgrade from Windows XP to Vista. If Microsoft's forecasts for the operating system are correct and Vista’s market share increases significantly, we could expect infection rates to increase further on Vista," added Clausen.

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