Samba AD can be corrupted by importing the ISC DHCP LDAP Schema (dhcp.schema) for OpenLDAP into Samba 4.x by using oLschema2ldif and ldbadd. Samba 4 will start, but every user will appear to have object Class Violations.
Created attachment 13223 [details] dhcpd OpenLDAP Schema
The command line used is: oLschema2ldif -b DC=pukey -I dhcp.schema -O dhcp-schema.ldif This converts the schemas followed by ldbadd /var/lib/samba/private/sam.ldb dhcp-schema.ldif
(In reply to Zombie Ryushu from comment #2) Closing this. It isn't a Samba problem, it is that the isc-dhcp schema is incompatible with Active directory, duplicate objectclasses.