I have a Windows 2008 R2 64bit server running as my KMS server with a Windows 2008 R2 KMS key(Volume_KMS_R2_B channel).
It has been successfully activated since June 15 this year. It has been working fine up until a few days ago.
Now the client workstations cannot be activated see attached image with error.
Has Microsoft released some updates that may need to get this functioning again?