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I have a laptop that's been acting up. (see here for details)

I'm hoping it doesn't come to this, but I may end up reinstalling Vista on it and was wondering what the procedure was for re-entering the license key. If I register the laptop again will Microsoft's online system squawk because the key has been used before? Do I need to call their installation 800 number and explain things? Hard to imagine they haven't heard a lot of false sob stories before so am not sure if that's the correct approach.

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up vote 1 down vote accepted

I believe you can re-activate as much as you want, automatically through the Internet, as long as you don't change the hardware too much.

You can read the facts on :

Microsoft Product Activation FAQ
Technical Details on Microsoft Product Activation for Windows XP

As long as your hardware is not "substantially different", reactivation will work. Just do not change the motherboard or the network card, which are counted as "substantially different".

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I reinstalled my version of XP on this new machine - new m/b - Intel vs AMD processor, new hard drives & new graphics card without a hitch. I think the frequency of re-activations comes into play as well. Having said that I'd re-activated on the old hardware a week earlier, but that was the first time in 5 years... – ChrisF Nov 15 '10 at 21:08

You may be able to complete the re-activation on line. It has worked for me a number of times in similar cases. Even when it did not, the phone call has been painless and MS has activated without issue. A few questions and it was "good to go".

If their system has seem a number of activations based on the key in question, you may have more of an issue.

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No, they wont really care. I'm not 100% sure about this, but supposedly, one license is good for 4 uses. (I will say again, I'm not 100% sure on that). If you need the license, you can download SIW (System Information for Windows). This will decrypt entries in your registry and give you keys, or whatever you need. If you need any help with this, let me know with a comment.

-Good Luck

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Thank you. I'll grab SIW and save my info in case I need it. – larryq Nov 15 '10 at 21:47

It depends on how you install it and your license.

If you use a restore partition, there is no problem. The restore partition has an OEM version of Windows and an OEM key for that manufacturer. The restore reverts your computer to just bought condition and the activation proceeds. The key isn't unique so MS has no way of knowing anything about your system and just activates it blindly.

If you restore from disks from your vendor - same thing.

If you have a retail (store bought) package - and reinstall on the same system - normally they just see the identical info and it goes through. They allow several reinstalls normally so as long as this is the first time it won't detect. If you have to call, they give you a new number normally with no problems.

If open license or volume license or enterprise - different things happen dependent on your license.

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