At the start of the year I setup a KMS server on a virtualised 2008R2 server. It was working perfectly for a while, clients activating etc., and then after about 4-5 months some strange activation issues started occuring. It was then I thought something was up with the KMS server so I uninstalled the KMS key (using slmgr.vbc -upk) then re-installed the key and attempted to reactivate which failed with the following;
Activating Windows Server(R), ServerStandard edition (68531fb9-5511-4989-97be-d11a0f55633f)...
Error: 0xC004F074 The Software Licensing Service reported that the computer could not be activated. The Key Management Service (KMS) is unavailable
When I Google that error code I only seem to get articles relating to problems acivating Windows 7 and Server 2008R2 against KMS servers installed on 2003/2008 Server which isn't really my problem.
So, now I have a KMS server that won't activate and I have Windows 7 clients which seem to be falling off as well. Happy to provide more details if needed.