Microsoft's Windows XP will control how many times users can reinstall the operating system by using an artificial intelligence engine, similar to those used to monitor credit card transactions, it emerged this week. The system will deactivate Windows XP on systems where the hardware has changed significantly, and could disadvantage many people in developing countries. The engine is part of Microsoft's plan to tie each copy of Windows XP to one specific PC. By preventing installations on different PCs, Microsoft has said that it hopes to crack down on software piracy. Current Windows licences are valid for only one PC, but there is no way to actively prevent people installing a copy of Windows on more than one PC -- for instance a home-built system -- a serious concern to Microsoft. Microsoft's solution -- called Windows Product Activation, or WPA -- will stop people installing a single copy of Windows XP on more than one PC. It will achieve this by using activation codes created from an image of the PC's hardware and settings. But the policy could also mean that users who upgrade, for instance, a graphics card and motherboard will almost certainly find that their Windows XP operating system will not boot when the PC is switched back on, it has now emerged. The new system, called Windows Product Activation, or WPA, first surfaced earlier this year in build 2410 of the new operating system, but few details were released as to exactly how it would work. Following widespread criticism from its corporate customers, the company last month said that those large customers on Open and Select volume licences would be exempt from WPA. However, companies and users not on volume licences will still be affected. Neil Laver, desktop marketing manager at Microsoft UK, has told ZDNet UK that "users will be able to change a few things on the PC but if they change too much the product will deactivate." "A new graphics card and new motherboard will mean the operating system will require reactivation," he said. To reactivate their operating system, users will have to send details of the installation, such as the product ID number and a hardware identifier, to a Microsoft-run clearing house. They will then receive a product activation code. If the product ID number is already registered against a different PC, the clearing house will not authorise the activation of the software. "We will know whether you have activated that particular copy of Windows before," said Laver. "If this is the second time then we'll reactivate it immediately, but if this is the 30th time you have phoned up to reactivate then it is obvious you are pirating and we will not reactivate it." Microsoft is still deciding what is a reasonable number of reactivations, and will use a back end artificial intelligence engine to differentiate between people who are innocently upgrading their PCs and those who are obviously pirating software. But, said Laver, the company cannot say exactly how many times a user will be able to upgrade how many components before their copy of Windows XP is de-activated. Many different criteria will be weighed up by the AI engine. For Internet-based registrations, the company plans to resolve IP addresses to the level of individual countries so that if it receives a request to activate a copy of Windows XP one day in the UK and again the next day in France, it would reject the second request. Laver said that personal information would not be collected. "If it is obvious there are three or four different machines we won't reactivate it," said Laver. "We have no problem with people changing hardware, but we want to stop the situation where people buy multiple PCs [and only one copy of Windows]." Microsoft has so far tested the technology in Canada, Brazil, New Zealand, Australia and China. Laver asserted that once people understand the process "they feel comfortable. The vast majority of users don't make very considerable changes to their PC -- most people don't make any change to their configuration at all." Customers who feel their copy of Windows XP has been unfairly deactivated will be able to enter an arbitration process, which Laver described as "a form of negotiation," with Microsoft. A freephone number will also be provided for complainants, but Laver conceded that only people in countries where the telephone companies provide freephone access. "Certainly most people in the developed world will have access but for others it will be a cost," he said. On the issue of the estimated 80 percent of the world's population that does not have access to a telephone, Laver said Microsoft research found that few such people use PCs. "The overlap of the people who would want a PC and don't have access to a telephone is virtually nil." Take a look at ZDNet's Whistler screenshots. Take me to ZDNet Enterprise Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet News forum. Let the editors know what you think in the Mailroom. And read what others have said.