People running Windows software will now need to provide a licence key before they can download any free Microsoft software.
Through Windows Genuine Advantage (WGA), Microsoft's anti-software-counterfeiting programme, users will need to prove their software is authentic by running an applet downloaded from the MicrosoftÊ website, which checks the licence keys.
Users found toÊbe running invalid licences will need to buy a legitimate copy ofÊWindows XP before they can download any Microsoft software.
Janet Gibbons, Windows product marketing manager at Microsoft, said the operating system will be discounted and will cost £91 for Windows XP Professional.
Users found to be running counterfeit software who are prepared to complete an online anti-piracy form and ship the pirated software back to Microsoft will receive a free copy of Windows XP Service Pack 2, she said.