Fix - Windows KMS Activation failure

In a lab environment, we run a Microsoft KMS server. We had built out an initial group of clients to meet the 25 minimum for KMS. Time passed and some engineers built out another group of clients, but everytime a client attempted to activate:
0xC004F038
The Software Protection Service reported that the computer could not be activated. The count reported by your Key Management Service (KMS) is insufficient. Please contact your system administrator.

The server did not show any errors and I could see the entries in the KMS log. I made sure the SRV record was in place, forward/reverse DNS was clean, and the system clocks were in sync. After some head banging, started digging into the Event details using the info below:


EventID: 12290
Logged by: KMS
Message:
An activation request has been processed.%nInfo:%n%1

HRESULT Return code 0x0
N-Policy Client product minimum count needed to activate 25
Machine Client computer name kms03.site5.contoso.com
CMID Client Machine ID e5c98033-aab6-4d0b-9af9-1d399597dd56
Client Time Request timestamp 2006/1/14 22:36
VM Info Client OS is running in a virtual machine 1
Licensing Status License status:

0 - Unlicensed
1 - Licensed (Activated)
2 - OOB grace
3 - OOT grace
4 - NonGenuineGrace
5 - Notifications
6 - Extended Grace

2
Time to Expiration Time remaining (minutes) 40123
ActID Activation ID - identifies the license cf67834d-db4a-402c-ab1f-2c134f02b700

That is when I noticed the "CMID" was the same for the different "Machines" attempting to activate. This was a result of the engineers spinning up copies of their VMs. The fix was simple enough, execute the following command on each KMS client, reboot, and try again:

      slmgr -rearm