This is the solution to activate Windows (XP, Vista, 7, 8 – Server 2003, Server 2008, Server 2012) when you have this message and you cannot activate it bacause your logged out.
This copy of Windows must be activated with Microsoft before you can continue. You cannot log on until you activate Windows. Do you want to activate Windows now?
Boot into Safe Mode. To do this, turn the computer on and press F8 as it is booting up. Go into Safe Mode by choosing the Safe Mode option.
Once you are at the desktop in Safe Mode, Click Start then click Run.
At the run command prompt type the following EXACTLY:
NOTE: The Oo’s in Oobe are oh’s – not zero’s. There is one space afterrundll32.exe. It is case sensitive as far as I know.
Wait a few seconds – the screen may blip a few times or so.
This just reset Windows Activation for 30 days.
Reboot the PC into normal mode – log in – re-activate Windows.