I have just installed Windows 8 in dual boot mode on my laptop. During Windows 8 Enterprise Edition installation I had no prompt to enter the product key.
Upon successful installation I was noted that I have to activate my Windows, but unlike Windows 7, I couldn’t find an option to change the product key.
Therefore I asked my good friend from Microsoft and I got the following answer.
Solution 1 (courtesy: tshepo)
Run the following command in Run prompt:
slui 3
The activation page will appear where you can type your new key. Activation should be automatic upon entering the new key.
Solution 2
Open CMD in elevated mode (run as administrator)
Type the following command:
slmgr.vbs -ipk PRODUCT KEY
Replace the PRODUCT KEY with your valid Windows 8 Enterprise key.
After successful message product key will be changed and Windows 8 will be automatically activated.