I want to buy a windows 7 online and upload the file. After uploading I would like to install it on a second PC with new codes. How do I save the files and use them as startup in the second machine. The reason for my action is that I have a genuine win 7 pro in my PC, but since I changed my motherboard, I had to use another version which is not genuine, so the winupdate is corrupting my PC and it won't start.