I was one of those who tried Windows 8 early and got a Windows Media Center key for free. Today through Dreamspark Premium I got a Windows 8.1 key. I normally used my new Windows 8.1 key and Windows 8.1 were activated successfully and because I remembered I had a Windows Media Center into my e-mail archive folder I used it in "Add features to Windows 8". Windows accepted the key, added Windows Media Center and rebooted. After the reboot, Windows 8.1 got deactivated and it won't accept my genuine Windows 8.1 Pro key. I do not wish to format my pc or re-install everything . I just want to activate my Windows 8.1. I do not care about Windows Media Center, I just want to activate them with my genuine key.
LOL if you just need the Windows 8.1 ISO, why are you requesting a Product Key? Aren't you able to grab the ISO from the internet?
OK, if I follow what you are saying, these things happened in this order: - you installed Windows 8.1 Pro and activated it with your valid Windows 8.1 Pro product key. - you ran the "add features" wizard, used your previously obtained WMC product key and it installed but isn't activated. Now that the edition has changed from Pro to Pro with WMC, you can't activate it with your Pro key. This is nothing to worry about. You have to activate it with a WMC key. If that WMC key was previously activated as an upgrade of a Windows 8 key, even if it was the same machine, and now you want to use it to upgrade a Windows 8.1 key, it won't activate online. This is to be expected, because activation is tied to the Windows that was upgraded. The solution is to activate by phone. It will ask you how many computers have you installed this copy of Windows on, you say "one." To get there, you can click the link in the activation window to contact Microsoft; or just type "slui 4" at the command prompt. Select your country, dial them up and follow the prompts.
Ultimately, this topic is of no use. It is everywhere answered about the phone activation. The op should have read the stickies and followed some posts by Faikee. Green people please bring in the lock. Thanks