Win 7 Activation AFTER installing SP1

I apologize if this topic has already been addressed, but after searching the forums for a few minutes, I was unable to find a solution for this other than calling MS directly.

I purchased an upgrade key for Win7 Home Premium x64 from MS around Oct. 2010 when it was first released. I was upgrading from Vista Ultimate x86.

I recently formatted and reinstalled Windows on my machine and went through the painful process of first installing Visa, then upgrading to Win 7. After a successful installation, I ran a seemingly endless number of Windows updates, of which included SP1. I did all of this BEFORE activation, thinking it should not have have any impact on my product key.

Well, I was wrong. After attempting to activate, I received an error message saying my product key was invalid and was "blocked" by Microsoft. Inside the activation window, there was a FAQ that said something about product keys being invalid if you tried to activate AFTER installing SP1. Is this really the case? My first thought was, you've got to be kidding me. Am I getting this error message simply because I had installed SP1 before activating my product key? I feel like this should not be this difficult.

Of course, all of Microsoft's offices are closed at the moment, and most likely will be tomorrow due to the US holiday. Therefore, I won't be able to activate this until Tuesday at the earliest. Not the end of the world....I have plenty of days left to activate before it requires me to do so, but this is still frustrating as all hell, considering I purchased my key through Microsoft and this was the only machine I have ever installed it on (no major configuration changes, etc.)

Before wasting any more time on this, I figured I would ask to see if anyone has encountered this problem and to see if there was any way to fix it other than calling stupid MS, which I consider to be a massive waste of time for something that should be so simple and straight forward.

Any help would be greatly appreciated. Thanks everyone.

No, installing SP1 and then activating shouldnt have any impact. Since you used the upgrade disk and you must have actually custom (clean) installed (inplace upgrade is not possible from 32 bit to 64 bit), you must have missed the workaround required to make the upgrade disk work. Since you have some time on your hands, I suggest you use this well-documented method to clean install and activate with the upgrade disk.

Clean Install with a Upgrade Windows 7 Version

Make sure any user data is backed up and yes, you'll need to update all over again, sorry about that. Next time download a full copy of SP1 and burn it to CD so it can be reused.

You can also try the registry workaround in Option 3 of that tut immediately, might solve your problem.

Hey Bill,

Thanks for getting back to me. I followed your instructions and those of the post you included and didn't have any luck. Was getting the same exact error message....as if I hadn't done anything at all. I came home from work this evening and as soon as I came over to my computer, a popup message in the bottom right corner came up saying Windows was successfully activated. I check the system settings via the control panel, and much to my dismay, Windows had activated itself. I still have no idea what the issue was, but it is resolved. Thanks again for your help.

Tyler