Change product key in windows server 2012 or windows 8

While playing around with some freshly installed Windows Server 2012 machines I wanted to Activate Windows, so clicked the appropriate option and it gave me an error. Had not yet entered a key, but saw that the activation wizard seemed to think I had a key (it displays the last few characters of the key). If you wanted to change the product key in previous versions there simply was a button for that with the activation wizard. That is gone now in Windows 2012 and Windows 8.
After a little search I found the first method and after a little more searching I found a KB article talking about this and other methods.
Solutions are all simple (if you know them):
1. Use slmgr

  • Open an elevated command prompt and type the following commands:
  • slmgr -upk
    This will remove the key first
  • slmgr -ipk xyzyx-xyzyx-xyzyx-xyzyx-xyzyx
    This will add your key. Of course replace the xyzyx-xyzyx with your own real key.
  • Activate Windows (you will probably have popups already during this process)

2. Use slui.exe

  • Swipe in from the right edge of the screen, and then tap Search. Or, if you are using a mouse, point to the lower-right corner of the screen, and then click Search.
  • In the search box, type Slui.exe 0x3.
  • Tap or click the Slui.exe 0x3 icon.
  • Type your product key in the Windows Activation window, and then click Activate.

3. You can also use the Volume Activation Management Tool (VAMT) 3.0 to change the product key remotely, or if you want to change the product key on multiple computers.
The last two methods I found referenced in this KB: http://support.microsoft.com/kb/2750773 (and the first one is to be found there as well in a way).
Would still be nice to get that old button back somehow B)
Bob Cornelissen