- Microsoft is to withdraw an anti-piracy tool from Windows Vista, which disables the operating system when invoked, following customer complaints.
The so-called "kill switch" is designed to prevent users with illegal copies of Vista from using certain features.
But the tool has suffered from glitches since it was introduced with many Windows users claiming that legal copies of Vista had been disabled.
Microsoft says its efforts have seen a drop in piracy of its software.
In a statement released by the company, Microsoft corporate vice president Mike Sievert, said: "Users whose systems are identified as counterfeit will be presented with clear and recurring notices about the status of their system and how to get genuine copies."
"They won't lose access to functionality or features, but it will be very clear to them that their copy of Window Vista is not genuine and they need to take action."
Microsoft has described the new approach as a "change of tactics". It said efforts to tackle piracy had seen numbers of fake copies of Vista at half the level of XP, the previous Windows operating system.
The change will take effect with the release of Service Pack 1, a major update to Windows Vista.