windows 7 asking for activation post install..

i installed it last week, thought i’d done the activation and now it’s asking me to start activate for windows. any ideas how to fix?
Answer #1
Just use another activator…Search in the Apps section..
Answer #2
said it all but to avoid any more unnecessary questions go here :
http://www.google.com?t=4208683&highlight=
scroll down til you reach the activators and choose one of them. Download, run and you’re good to go.
Cheers