As Microsoft is readying its "Windows Genuine Advantage" technology that will prevent access to some updates for users of illegal copies of Windows, it turns out that there is a fairly easy way to circumvent the technology.

The technology requires users to run an application. After it has determined that you're using a legitimately licensed copy of Windows, you'll receive an authentication code. Enter the code in a form on the Microsoft website and your system is authorised for the rest of its life.

Now grab your notebooks: the workaround allows you use the authorisation code on any computer, just do it within a few hours, because the code expires "quickly", a Microsoft spokesperson told vnunet.com.

Because code has limited use (it expires), Microsoft doesn't plan to fix the workaround, he said.

Users however can circumvent the expiration time by setting changing the system time on their computer, claims security expert Debasis Mohanty in a posting on a security email list. Just make sure you write down when you requested the original authorisation code.