The Virtual Machines available for download is for 180 day evaluations. Additionally they will require activation, or re-arming, after a 10 day period after which they will shut down after 2 hours of continuous operation. To "re-arm" the Virtual Machines use the shortcut provided under Start > All Programs > re-arm > Re-arm Windows (restart required). This will reset the grace period for 10 days. This can be done twice.