What’s The Difference Between Windows 7 Home Premium Upgrade And Windows 7 Home Premium?
I preordered the Windows 7 Home Premium Upgrade a while ago and later on, I saw that there was also a regular Windows 7 Home Premium for almost double the price. Just wondering what the differences between them are because I couldn’t find any. (Besides the price difference.)

You need a prior genuine version of Windows to use the upgrade version. It will do a check for it.
You’d use the full version if you don’t have one, for example if you’re building a computer for someone and putting in a blank hard drive.
You can use the upgrade disc to install it if you already own a genuine copy of Windows 2000, XP, or Vista. If you do not have a genuine copy of one of these Windows versions, you must buy the full version.
To use the upgrade version you have to have a qualifying operating system currently to upgrade from, either Vista or XP. If you don’t currently own one of those two, you cannot use the upgrade version.
An upgrade version is meant to upgrade an existing operating system. You will have to have a legal copy of a previous Windows version in order for it to work.
You need to have a previous (genuine) version of Vista or XP. For more info, check out this Windows 7 FAQ page: http://www.microsoft.com/windows/buy/off…