Yes, the computer in question that I have was a fresh install from the Anniversary Update. I never enter keys during the install and instead wait until I have all drivers, updates, and software installed. Then I activate. The install currently on the computer took the key and activated it. However, it now has the following message:
We can't activate Windows on this device as the previous version of Windows was not activated prior to upgrading to Windows 10. Go to the Store to buy genuine Windows. Error code: 0x803F7001
I'm still working on the Windows 7 VM.EDIT:
Well, turns out I was able to just enter the same exact key on the Windows 10 install and it now shows Activated. I'm going to keep an eye on it to see if it stays...particularly after the Creators Update.EDIT 2:
I'm running the Update Assistant on that PC to force the Creators Update now.