After installing DHCP on Server 2012 R2, you get this error:
Volume Shadow Copy Service error: Unexpected error calling routine RegOpenKeyExW
Event ID: 8193
There’s a couple of things I’ve found on the net about this one, the first suggests that you just need to give permission for the NETWORK SERVICE account and the user account that you set up DHCP with, to give full access to the following registry location: HKEY_LOCAL_MACHINE -> System -> Current Control Set -> Services -> VSS. Also I found this Microsoft article suggesting you take a few more steps.
I only did the first, which seemed to fix it.