We use Win 7 on the laptop and XP on the desktop. We have found that very commonly while on the laptop running Win7 and IE we cannot complete a purchase on an order as the step link to actually 'buy' does not complete and sits there offering a blank screen. Moving to the desktop with XP and IE the process is smooth and easy. We've run the registry cleaner and full AV scan and still can't get it to run normally. However, on ebay this does not seem to be a problem.