A fault on a Microsoft domain name server has prevented users from downloading a software patch for Windows XP leaving them open to serious attacks.
Microsoft engineers created the problem as they attempted to update software on a server. Since then, the glitch has prevented users from downloading software updates.
According to Microsoft, eight million users download software updates each week.
The software giant confirmed last month that Windows XP, touted as its most secure operating system, had a serious vulnerability in its Universal Plug and Play (UPnP) software. The server problem has prevented users from downloading this patch.
The UPnP hole could allow an attacker to take over a networked computer, view or delete files, or launch denial of service attacks which cripple a PC by flooding it with data.
Analyst firm Gartner rated the vulnerability as 'high risk', and advised business clients to hold off XP deployment for a couple of months to see if further holes became apparent.
UPnP uses internet protocols to allow devices such as computers, scanners and printers to automatically discover one another so that they can communicate.
In the US, the FBI's National Infrastructure Protection Center urged XP users to disable the UPnP feature.
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