Recently I had a problem with my Windows 7 clients (built with my new and freshly created image) where they would not get activated by the KMS server. After some research I noticed that the KMS counter was not updated with new client and so my KMS server would never reach the point where it would actually start activating my clients (25 clients).
The reason for the KMS server not updating it’s counter was the fact that all my clients where reporting to the KMS server with the same Client Machine ID (CMID) which I noticed trough the events it reported in the Key Management Service event log of my KMS server.
If you ‘Bing’ on this one you will get lot’s of posts where this is due to the sysprep command which is not ran with the /generalize parameter. This parameter removes all hardware dependencies and when building a new client, it will create a new CMID.
However I did use the /generalize parameter so why do I get the same behavior. The solution is simple but it did take me some time to notice that I seemed to have missed the <skiprearm> setting in my xml answer file. This setting should be removed before using the image in a production environment! If not you’ll end up rebuilding your image like me…
More info: http://support.microsoft.com/kb/929829