The thing I liked about the Vista/7 activation system was that it let you “try before you buy”, much like many of the laptops that come with 60 day Office 2007 trials. You can load all your old files, install all your favourite programs and see how well they work, and so on. Unfortunately, with Windows 7, I have found that this is not the whole story with delayed activation; let me tell you how I broke it!
If you are doing the above for testing purposes, but are fully intending to activate the machine assuming there are no problems, then you won’t enter your key when you install (just in case windows sneakily activates before you are happy, and then there’s a problem).
However, the standard install disk for Windows 7 has all the different editions in there, Home Premium, Professional, Ultimate, and so on. It actually chooses which version to install based on the key you enter; if, like me when testing, you don’t enter one, it installs ultimate, which means that the home premium/professional license you have will fail to activate with a “you must buy a Windows 7 Ultimate license” warning.
Gah! So how do you downgrade your new installation (which you just spent ages configuring, installing all your games, building cygwin, and generally massaging into a usable windows install)? Oh bad luck, you can’t! You have to reinstall from scratch!
Now on that thread it says the disk will let you choose – not so my friend! There are no warnings (or if they are then I missed them in 2 RC installs and 2 final version ones)!
So just in case you are installing in a testing environment that might become a proper environment in the future – make sure you can activate before you invest too much of your life setting up the machine!