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

Theoretically, can you activate Windows XP, Vista, 7, on identical machines? For example, if peter and tom got the same machines at BestBuy, can they activate Windows 7 on both machines since the hardware ID / fingerprint is the same?

I think the normal use is to activate it multiple times on the same machine on different partition, for example, if Win 7 on one partition is slowed down by various app installation, then reinstalling Win 7 on a different partition as a fresh start is allowable.

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marked as duplicate by studiohack Jun 28 '11 at 1:07

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

up vote 20 down vote accepted

No. The hardware signature uses data that includes includes system specific things like the NIC card's MAC address and the CPU and hard drive serial numbers.

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I have a vista installation disc that came with my machine. Why is it that I'm able to install and activate it just about anywhere I want? – Malabarba Nov 1 '09 at 15:47
You can activate it on different machines but the total number of activations is limited (5 for XP, I'm not sure how many for Vista.) Each additional machine or a substantial change to a single machine that changes its signature uses one activation. – Chris Nava Nov 2 '09 at 3:50


Even if you bought the same computers, still they have different ID's.

It is totally against the EULA of Windows 7.

What you COULD do is buying a family pack, then you CAN legally install it on more machines. Obviously this will cost you more money.

Hope I could help.

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Installing the same Win7 key on multiple machines is against the EULA. Also, I'm pretty sure that even if the machines are "hardware identical" the hardware will still have different IDs generated.

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They're not 100% identical, even though you percieve them as such. The OS probably also looks at serial numbers which are unique. That way, 2 identical machines are still totally different to the activation process; if you install on the same machine that's not the case. One good example of having different serial numbers is the motherboard; you can see a thread here where getting the serial number is discussed.

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According to the EULA, The only "second machine" you can install Windows 7 on is within a virtual machine, on the same host in which the Windows 7 copy is already installed.

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If you mean according to the license permissions, you should say so. The way you said it, it sounds like a physical limitation which no one could fix, even if they wanted to. In fact, microsoft could be much more liberal about this. – Lee B Oct 25 '09 at 10:22
I think it's obvious I meant that but edited regardless. – John T Oct 25 '09 at 13:44

Yes you could.........BUT there are no two IDENTICAL computers. Serial numbers differ between otherwise like computers and that prevents doing what you suggest!

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You just activate, then clone the hard drive. No big deal. Works with XP, Vista, it should work with Win7 as well.

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Yes, technically, you probably can. You might have to call microsoft licensing and ask them to help you activate the new machine (because, say, you had to replace your previous computer, due to a mainboard problem that you don't fully understand ;). But I'm not sure if the old computer would still be able to go online and get updates once the new one was activated. I think it would work fine though.

Even if just using the software as permitted by the license on one machine though, the DRM is a big inconvenience. Upgrading some components on your own computer can mean having to call microsoft and justify yourself to them. It's much easier to just apply an activation crack.

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