nk497 writes: "The release candidate for Microsoft Windows 7 will expire June 2010, and the software giant will let users know they need to pay to upgrade by shutting down the system every two hours for three months. According to Microsoft: "The RC will expire on June 1, 2010. Starting on March 1, 2010, your PC will begin shutting down every two hours. Windows will notify you two weeks before the bi-hourly shutdowns start. To avoid interruption, you'll need to install a non-expired version of Windows before March 1, 2010. You'll also need to install the programs and data that you want to use.""