I recently updated from Windows 8 Developer Preview to the full version. Instead of doing a direct upgrade or installing from scratch, I burned Windows 8 to a CD and through the options given, told Windows 8 that I’d like to upgrade without saving any any old data, apps, profile information. I was basically installing from scratch, but the Windows 8 was saving my data off to the side in a Windows.old file.
I started up my new installation of Windows 8 and began editing my profile, but was warned that I wouldn’t be able to personalize anything until I activated my account. When trying to activate, I was given the error “Windows cannot activate right now. Try again later” – or something along those lines.
Through some internet searching, I learned that I needed to run the following command as an administrator:
slmgr.vbs -ipk "YOUR_PRODUCT_KEY"
After running the command, my product was activated and I could do anything I wanted. I rebooted for good measure. Screenshot below for you visual folks: