I was just trying to keep a fresh up-to-date copy of the OS ready in case my working hd crashed. Is this possible? I'm currently experimenting with this as I've already installed it on the two different drives, but the second clean install won't validate? Is this a restriction by Microsoft, is it a limit of one upgrade install over the beta or is it tagged by first hard drive hardware ID? I'm currently running the Win7 Home Premium Upgrade (clean install over the beta that I was running). The working install is on 2 ea 150 GB WD raptors in RAID 0 (working fine btw) and the 2nd backup install is on a 500 GB SATA Seagate drive. When I installed it on the 2nd, I had previously made an image of the working beta and restored it to the 500 GB drive before running the upgrade which installed fine but I find it won't activate; tells me I should call MS 'cause it might be pirate... ack! I apologize if this has been addressed elsewhere. I did browse quite a bit before posting. Thanks in advance!