That message is only coming if you have a Serial Number for KCLT in the registry. If that's a proper Serial Number for KCLT, you just activate it and, if it fails the activation for any reason, it won't be stored in the registry, unless it pass activation.
So, it seems you must have inserted a wrong Serial Number for KCLT by changing the registry manually, so it stays there, repeating the question to activate it.