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Without a product key being labelled, is there is any way to identify what Microsoft software product a given product key is meant to activate?

Let's say for example I had the product key ABCDE-FGHIJ-KLMNO-PQRST-UVWXY, but I had no clue if was meant for Windows 7 Ultimate, Windows 7 Home Premium, Vista Ultimate, or even Office 2010. Is there a way I identify the software product the key is meant for (or at least get a good estimate)?

Note: I have searched and searched many times on the Internet, but the only results I ever find are how to recover a lost product key by using something like Nirsoft ProduKey. This is not what I am looking for.

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I recall that when XP first came out, there was a tool (“blue-list” iirc), that had a key-validation function for different editions of XP and Office. However, I think I remember reading that later on (e.g., after SP1 or 2), some valid keys would no longer validate because Microsoft had changed the algorithm. – Synetech Dec 9 '12 at 4:27
up vote 12 down vote accepted

Unfortunately there isn’t. The product key sequence is according to a mathematical algorithm. The product key is a partially random, 25-character alphanumeric code, specifically designed to defeat against keygens and leaked serial numbers. The code has three (known) components:

  1. An actual serial number
  2. Verification data (using modular math)
  3. A checksum (CRC) for typos

There are several good references to how product keys are utilized. This one is particularly good.

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I would contact Microsoft themselves about this, I don't know of any tool or method for end users like us to do this. The other option is to install, preferably in a virtual machine, all the possible software that it could belong to and see which one "takes" it.

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VAMT 2.0 allows administrators to automate and centrally manage a range of activities related to Windows client, Windows Server, and Office 2010 activations.

To see what it looks like and how to make it work, check out this link

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