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When installing Windows 7 or Vista, does the language, version, architecture (64-bit or 32-bit) or source (OEM, retail, or MSDN) matter?

I run three computers through one router. Do I need to buy a 3 licence version of Windows 7 software, or can I instal a single user version 3 times?
I mean, I have re-installed my own copy of Windows XP about 6 times, on different computers, all used by me, at the same address. So what's the difference?

  • 2
    BTW you probably aren't supposed to install multiple copies of XP either - at least not have them in use at the same time. Just because you can doesn't mean you should. I mean I could get in my car and drive on the wrong side of the road at very high speeds through my town's main street right now if I wanted to. But the fact that its possible for me to do that doesn't make it "right" or legal.
    – Rob Moir
    Jan 30 '11 at 18:24
  • Reinstalling is one thing, having XP on more than 1 PC at a time with the same license is another, no it is not legal to do so.
    – Moab
    Jan 30 '11 at 19:27

Yes. A licence should only be used on one computer. You can reinstall this as many times as you want, and you can format the disk on which it is installed and install it on another computer. But you can't have one licence installed on more than one computer at a time.


The difference is that Product Activation on Windows 7 is much more efficient than it was in XP.

It is not advised to install it on more than one computer, unless you really like Microsoft to black-list your serial.

It is also not advised to move the same serial from one computer to another too frequently, as when you replace the computer. So better leave it for at least 3 (or 6) months on each computer.

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