I needed to remove the license key for NCover on one of our build machines because the license was moved to another build machine.

I didn’t find anything using Google, so by trial and no error deleting the value named Key from the key HKLM\SOFTWARE\Gnoso\NCover did the trick with NCover v2.1.

I’m writing this down so I know how to do it if I need to do it again, and for anyone else’s reference.