I'm trying to upgrade my PC from Vista Enterprise SP1 to Windows 7. When I start the upgrade from within Vista it tells me it is copying Setup Files to my computer. Initially there is activity with the CD/DVD drive and then it stops. The screen continues to say Setup Files are copying but activity on the CD/DVD drive has stopped. I have let it sit for several hours but no change. I can't tell what is going on or what to try in order to dislodge and make progress. Any suggestions would be greatly appreciated.