Many people while trying to Reinstall Windows 8 Developer Preview are being asked to enter Product Key and are not able to proceed without skipping this step. This might also happen when using the Reset functionality. As I could install in my first try so the case didn’t arise for the Product key and as such Product keys
For this the Microsoft Support has provided these Product keys -
If you are running a Server version of Windows DP then you can use this key -
Also you can find the Product keys in a PID file when you go to the Sources folder of the ISO burned disc.
For many these Product keys didn’t work, So please note that the first time install might have failed due to mismatch in SHA1 so please verify this and also error during ISO burning so burn the ISO at lower speed and check the ‘verify after burning’ option if you are using the Windows 7 inbuilt burning. This has worked for many .