In March 2012 I purchased a Windows 7 upgrade from the Microsoft Store. That computer stopped functioning in June. I bought a new computer with Windows 7 Professional 64 bit. I wanted to take the Windows 7 upgrade and use it on another computer. However, I did not have the disk and required another download. I contacted Microsoft.
Microsoft told me that once you apply their system to a computer you cannot transfer it. In other words if your hard drive fries and is un-restorable you are out of luck. Unless you bought the product in a store and had a CD in which to download it from. Microsoft said that once it was loaded on a computer it could never be used on another machine. It was if a symbiotic relationship had occurred between that groupings of components and the software.
After talking to the manager and nearly an hour of my time, I hung up wishing that there was another operating system available to support all of my computers.
I have been with Microsoft since the days of DOS and have never been treated in such a manner. My suggestion to all of you is if you buy any Microsoft products that you get a copy of the software as part of the purchase and never call their support people, especially if you have a bad heart.
Review about: Microsoft Software Upgrade.