Windows activation is simple and straightforward if you understand the components. I have had a few customers that stumbled when getting a KMS online and in every case it has been an issue with name resolution, network connectivity, or they simply did not understand how to use the keys.
Activation is designed to help you with deployments and sustain your environment even in the event a key gets lost. KMS is the simplest of all the activation methods because you only need to worry about putting a key in one machine. You can then deploy new machines without having to ever worry about keys unless your device will be off the network for more than 6 months.
This is the first of a two part series to break down KMS troubleshooting in to a process that should help identify exactly what is at fault. I don't want to mislead or instill fear to those who are just starting out - the process is normally simple by design. However, for those who have run in to trouble, I'd like to publish a guide that will help you isolate and correct the issue you've encountered without spinning your wheels. Part 2 will be published next week with a focus on troubleshooting the server.
Microsoft, KMS, Troubleshooting, Knowledgebase, Article