I recently encountered a user who had completed an installation of Windows 8 but hot not yet entered their Product Key. As a result, the OS was displaying messages telling them to Activate the product. Furthermore, they reported that clicking Activate in the System settings of the Control Panel yielded the following error:
“DNS name does not exist.”
I wasn’t sure what this message meant, but I noticed that the last 5 characters visible on the Activation Center screen (see below) were incorrect. So I got the correct key and figured I’d give it a try.
To my surprise, I found that in Windows 8 Microsoft removed the GUI link to the window which allows us to change the Windows Product Key. Instead, you have the two following options.
1. You can launch a window that will allow you to key the new code by running the Command Prompt ”As Administrator”, typing “slui 3”, and pressing enter.
2. You can enter the new Product Key at the Administrator Command Prompt using the following command: slmgr.vbs –ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx
Why Microsoft made this harder on us, I do not know. But, hopefully, this may save you some time.