I recently installed Windows 8 Enterprise in my company. During the installation, setup does not require input of serial number/key. So when Windows installs, you must go through procedure of changing the key, and activating Windows.
So here it goes.
On Desktop, go with your mouse to bottom left corner. When Start icon pops up, press right mouse button and select Command Prompt (Admin).
Now you must run VB script to change serial key: (X-es represent your key)
Now all that is left to do is to activate your windows. Also through command prompt, and with the same
VBs script, but with diffrent switch.
After hitting the Enter, the pop up will tell you that Windows were activated successfully.