Windows Product Key doesn't work on other Windows - Super User most recent 30 from 2018-06-21T06:07:55Z 1 Windows Product Key doesn't work on other Windows Dennis K. 2013-02-05T22:40:27Z 2013-12-19T16:31:46Z <p>My situation is as follows: I have three license keys for Windows: </p> <ul> <li>(A) 1 Windows 7 Professional</li> <li>(B) 1 "Microsoft Windows 7 Professional with Service Pack 1 32/64-bit (German) - DreamSpark"</li> <li>(C) 1 Windows 7 Home Prem OA</li> </ul> <p>Now I had a computer that ran with my (A) license for some years, anyway last month I bought a new laptop which I will use instead of the computer. The laptop came with license key (C), but since I didn't want all programs and the stuff that comes with a new Windows on it, I formatted it, using my (A) product key.</p> <p>In hindsight, that was not such a brilliant idea as I now see, because apparently I cannot use the older license (A) for the activation of my new laptop, since it is already connected to the old PC.</p> <p>But I have got license (B) from my university which offered a free license for every student, I requested (B) about one month ago. Nobody ever used it and I didn't share it with anyone. Now it appears as if it is not compatible with my current version of windows on my laptop, although both are Windows 7 Professional. When I try to activate my product by changing the laptops' product key to (B), I get the error message that this key is not a valid key DESPITE the fact, that I copy-pasted it from the Dreamspark page where I got it from.</p> <p>So there is no possibility of misspelling or anything, what could be the reason for the problems I have?</p> <p><strong>EDIT:</strong> I just want to get my laptop run with a valid product key without re-formatting it. If there is a possibility to get (C) running via an upgrade or something, I really don't care which Windows7 I will use. Fact is, that I have 3 product keys, but the laptop is not activated, which I want to change.</p> 1 Answer by Fraser for Windows Product Key doesn't work on other Windows Fraser 2013-02-05T22:57:49Z 2013-02-05T22:57:49Z <p>The licence keys are specific to each version. You can't use a key from one to activate another. Although <code>A</code> and <code>B</code> both represent Windows 7 Professional, they are almost certainly different versions. That is the reason for the <code>B</code> key being not valid. To clarify, it is a valid key, but not for version <code>A</code> - it is only a valid key for version <code>B</code>.</p> <p>You can't upgrade to <code>C</code> from <code>A</code> as <code>A</code> is already an upgraded version of the OS (pro/home). It would be a downgrade and AFAIK this is not possible.</p> <p>The only way you can do this is via manual activation on the new laptop of licence <code>A</code> to transfer it. However this will deactivate the old computer.</p> <p>There is no way to have both machines activated using the same OS whilst using keys from differing versions.</p> <p>Unfortunately your best bet would be to back up your personal files and then re-install that actual OS that you have a free key for.</p> 1 Answer by Dennis K. for Windows Product Key doesn't work on other Windows Dennis K. 2013-02-06T08:54:12Z 2013-02-06T08:54:12Z <p>The problem is solved without transfering the license key or re-formatting my laptop:</p> <p>It appears that the problem existed in the fact, that the current product key <code>A</code> was a key for the <em>Windows 7 Professional</em>, in contrast to <code>B</code>, which was a key for <em>Windows 7 Professional <strong>with Service Pack 1</strong></em>.</p> <p>It seems impossible for Windows to detect the fact that both are in fact the same OS unless I have the Service Pack 1 installed. Now the solution was this: </p> <ul> <li>I installed the Service Pack 1 to my Windows 7 Professional, let it pass the configuration and waited until it was ready and logged in. </li> <li>After that, I tried to activate the system with the license key <code>B</code> again (for Windows <em>with</em> Service Pack 1) and it was able to activate the product online.</li> </ul> <p>Long story short: <code>A</code> is not equal to <code>B</code>, but with the installation of Service Pack 1, the current version of Windows became compatible with <code>B</code>, so I got it activated.</p> <p>Thanks anyway to everyone who helped in comments or answers!</p>