KMS help

Environ is Windows 2008 R2 domain.  All DCs are 2012 R2, but forest and domain functional level is 2008 R2.

We have one KMS server.

slmgr /dli all shows only three products we are licensed for:  Office 2015, Server Standard Edition and Office 2010.

However, I have installed our KMS key for Windows 7 and it shows in VAMT as a CSVLK.

My new Windows 7 machines are not activating.  The PC reports 0xC004F074 which is "Troubleshoot all 122888 errors in Event Viewer"

Event Viewer on the KMS host shows a 0xC004F042, which is "This error occurs when a KMS client contacts a KMS host that cannot activate the client software. This can be common in mixed environments that contain application and operating system-specific KMS hosts, for example."  That doesn't really help me troubleshoot the issue.

Problem 1, my Windows 7 KMS key is not showing on my slmgr /dli report and my Windows 7 machines are not activating.

Problem 2, I'm not sure how to troubleshoot the vague error codes.

This is becoming a crisis as I have machines about to need to activate against KMS again.

Any thoughts or help would be greatly appreciated.

Thanks

Cliff