After the installation of Windows 8 there was an error when I tried to activate:

“Activation Error: Code 0x8007232b
DNS Name does not exist”

The support pages from Microsoft pointed to the following solution:

Use MAK(Multiple Activation Key) instead of KMS activation.

Run command prompt as an adminstrator and enter the following command where xxxxx-xxxxx-xxxxx-xxxxx-xxxxx represents your MAK product key.:

slmgr -ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx